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Azul ultramarino

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Kai y Ren se conocieron en el primer año de secundaria y, desde entonces, han sido compañeros de clase. Su amistad es total, pero, al llegar al último año de instituto, resulta que dejan de compartir aula. Esta inesperada separación hará mella en ellos, que por primera vez son conscientes de lo que sienten... pese a lo cual optan por ahogar sus sentimientos por temor al rechazo del otro.

Si nada cambia antes de final de curso, deberán decirse adiós probablemente para siempre.

178 pages, Paperback

First published February 28, 2015

19 people are currently reading
708 people want to read

About the author

Nagisa Furuya

17 books324 followers
Nagisa FURUYA (古矢渚, Furuya Nagisa) is a Japanese mangaka.

See for her doujinshi works under circle PLUG.

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5 stars
389 (25%)
4 stars
636 (42%)
3 stars
408 (27%)
2 stars
55 (3%)
1 star
10 (<1%)
Displaying 1 - 30 of 334 reviews
Profile Image for daniella.
212 reviews440 followers
January 9, 2024
3stars⚝

Kai and Ren have been in the same class since middle school, but in their final year of high school, they're not in the same class anymore. Kai feels like he and Ren are growing apart. As the story unfolds, they both realize they have feelings for each other. It's such a sweet journey of self discovery! 💕

Having both perspectives in this manga really added depth to the story, especially considering its length. It would have been amazing to have more backstory and delve even deeper into their friendship. I wanted to know more about their journey and the moments that brought them together. . But for what it was, this was a solid cute read. I couldn't help but get all excited and giddy towards the end!

My favorite scene would be where one of them confesses their feelings while the other is sleeping🤭

Thank you to netgalley and the publisher for an arc in exchange for an honest review!
Profile Image for daph pink ♡ .
1,301 reviews3,283 followers
August 14, 2022
A story from my favourite bl manga artist that is sadly underappreciated. Whether it is cliche or not, the story of childhood friends who become lovers has always been one of my favourites. The deeper you go into the plot, the more you will adore it.

The sequences where they tell how they met and their pasts are some of my favourites. I've always praised the author's talent for wonderfully expressing emotions through her works, and this manga was no different. Despite the slow pacing of this manga, I really enjoyed it because it allowed the characters to grow and express their emotions. It also allowed me to feel connected to the characters and the events happening around them, which was a good thing in my opinion.
Profile Image for Brooke.
830 reviews560 followers
January 9, 2024
⭐️ 3 stars ⭐️

Cute friends to lovers YA manga.

Manga is something I want to love, but somehow most of the time end up liking them at best, with very few exceptions.
My Ultramarine Sky was no different.
The art style was pretty, the characters cute. There just wasn’t much to the story.

The pining in the beginning was honestly the best part. The rest didn’t bring out the emotions I was hoping for.

I received a free copy of this book from NetGalley, and am leaving this honest review voluntarily.
Profile Image for ♡ Martina ♡.
295 reviews370 followers
April 27, 2022
Nagisa Furuya si riconferma la mia mangaka preferita.
Adoro il suo stile, le sue storie, i suoi personaggi ma soprattutto i suoi disegni.
Ren e Kai sono amici fin dalla prima media e il loro rapporto è cresciuto con loro nel corso degli anni ed è diventato sempre più forte finché la loro quotidianità non viene spezzata.
In solo volume, Nagisa Furuya è riuscita a creare una storia d'amore molto profonda fatta di piccoli gesti, parole e sguardi furtivi tra i protagonisti.
Mi piacerebbe un seguito su Ren e Kai e l'evolversi del loro rapporto durante gli anni dell'università.
Profile Image for Lauren Lanz.
897 reviews308 followers
February 5, 2024
A cliche yet wholesome high school romance! Anything involving childhood friends to lovers immediately has my interest, so I’m not surprised to have liked this. Ren and Kai were so considerate of each other in a way only best friends are; any miscommunication between them was short lived, and their brief confession + romance was really sweet. For a one shot, this was pretty good!
Profile Image for Keiko, the manga enthusiast ♒︎.
1,267 reviews187 followers
July 20, 2023
APPARENTLY, THIS IS THE 3RD TIME THAT I HAVE REREAD IT. AND APPARENTLY, THE FIRST AND SECOND TIME I READ IT WAS 2 YEARS AGO WHEN I WAS STILL A LITTLE BUD, HUNGRY FOR BL STORIES, AND I JUST ADORED EVERYTHING NAGISA FURUYA CREATED. And apparently, I read it 2 consecutive times without getting bored. again after two days of ultramarine lovesickness. I just miss the whole gang so much. This morning, I randomly thought of an ultramarine sky and felt the need to read this one again. I thought about not marking this read for the 3rd time but I realized, I'm robbing every damned fujoshi and bl enthusiast of getting a chance to meet this gorgeous book that I have loved, [and love still,] two summers ago.

AND SENSEI, I NEED A VOLUME EXCLUSIVELY ABOUT ANDY, I ADORE HIM STILL. He's just so angry and a high-blooded beast all the time, wanting to have a girlfriend too, and I'm anticipating a bl story to come out of that concept. That would be too hilarious.

December 18, 2021 at 8:03 AM
Review 2

Re-reading because I need to see Kanamecchi and Andy this time! And! I came back to read my favorite line once again:

You are my life. My world is incomplete without you. You are my ultramarine. You are my everything.


Swoon! It makes my heart melt. Thank you, Nagisa sensei. This is really my favorite among your works. Although, all your works closely follow. I love them all.

Such a same, I did not keep my first review.
Profile Image for aria ✧.
921 reviews155 followers
March 1, 2025
It may have been on a whim, or said out of convenience. Yet, for a person who always goes at his own pace, and is never attached to anything…To choose the place where I am…That makes me so happy. Like a cat who has slowly warmed up to you. Slowly. However, I was honestly moved. By the time I noticed, it had extended beyond feelings for a friend.


Nagisa Furaya has a way of writing the softest, sweetest yet angsty romances in such few chapters. "All About Ocean Blue" follows Mizushiro Ren and Makihara Kai who have been friends since middle school. They found themselves in the same class throughout the years and when it’s time to join high school, Ren follows Kai to his school where they are unfortunately put in separate classes.

There’s this running joke where Kai and Ren would roleplay a bl drama when with their other two friends but for Kai, those scenes are not a joke. He’s had feelings for Ren for a long time but hides them to maintain their relationship. The pining! It was so angsty! When Ren got a girlfriend and Kai cried as he wrote to him a congratulatory message broke my heart. I don't like how the author made it seem like they were horrible people for breaking up with their girlfriends when they realised they'd fallen for the other. Their relationship was so beautiful to read about. He was his ultramarine. He was his everything.

You are my life. My world is incomplete without you. Even if someone else were here, I hate it if you’re not the one next to me. So…So, don’t say it was a mistake to fall in love with me.
Profile Image for Dilushani Jayalath.
1,029 reviews197 followers
May 31, 2022
As always, Nagisa Furuya's books are very cute and has a small dash of realistic notion to it. One of my favorite things about her work is that they are easy to read while they still have a strong emotional impact. It maybe just few chapters (most of the time less than 10 chapter even) but you'll be left short of breath due to the sudden emotional punch. Gunjo no subete gets one less star due to the fact, I was confused if Ren truly loved or was he going along with the fact that they have been together for so long that they need to be together as a couple too. Unlike her other work, I feel like this one left few question unanswered but I still liked it nonetheless. Now let me jump right into another one of her short mangas. See you on the other side!
Profile Image for donutdot.
491 reviews13 followers
January 22, 2024
thanks to netgalley and the publisher Kodansha for an e-arc

single volume mangas always hit different. they already have so few pages, and the medium itself limits the number of words that can be used. yet, somehow My Ultramarine Sky managed to convey the deep yearning between Kai and Ren so profoundly, as well as what it means to 'take for granted' what we thought would always be.

i've always had issues with that personally. whenever i graduate or change classes, i always think that i'd just continue my days as per normal and somehow i'd still be in contact with everyone i know. well, that's a lie. and seeing how things between our two protagonists change once they get into different classes, something they never thought would happen, just because they thought things would always remain the same, hurts deeply.

i loved seeing both sides of the 'x fell first, y fell harder' trope. clearly, Kai is the one who fell first here, having resigned to keeping his feelings in check for Ren for the rest of his days. it didn't occur to me the pain that he's always carried, something that should always hurt, has become normal for him, to the point where he pulls away from touching Ren casually (outside of their usual BL plays in front of their friends, which are hilarious and a nice meta touch on the contemporary romance tropes).

seeing the pay off where Ren is hit with his sudden awakening after Kai distances himself from him was very relieving, and i especially loved that Ren is the one who took the initiative to seek Kai out to resolve the misunderstanding and FINALLY get together.

the bonus chapter of the two of them playing shogi (and their first kiss!!) was very sweet, and i always love content of a couple living out their days after getting together!!
This entire review has been hidden because of spoilers.
Profile Image for Keiko, the manga enthusiast ♒︎.
1,267 reviews187 followers
July 8, 2023
OH HOLD UP!!! "YOU ARE MY ULTRAMARINE. YOU ARE MY EVERYTHING" IS COMING IN ENGLISH TRANSLATION. 💙💜 MY ULTRAMARINE HEART IS HAPPY, SENSEI.
Profile Image for suvi.
649 reviews
September 4, 2025
y'all I was reading this yesterday while waiting for my bus when a drunk man decided to start harassing me. I put my headphones on, ignore him and continue reading my book. You know what this dude does? He then forces his way into the empty seat next to me, despite the fact that I placed my bag there and the bus is half empty. I put my music on a little bit louder and pretend I don't even notice him because I am so interested in my book - we move on, okay? No. This dude gets off on the same stop as I do AND follows me. How do I know he followed me and wasn't just on his way home? There are only handful of houses in the direction I go to, I kinda know who lives in which house and I had never in my life seen this man before. And when I took a wrong turn through my neighbours' street which kinda just circles back to the "main" walkway and means I would have come face to face with him but he was gone. Which means he must have done an U-turn, otherwise I would have still seen him.

SO to the book. It was sweet, I liked it. And all I could think about was that it really isn't the worst book to be the last one I might ever read. And it truly isn't the worst book at all to be found next to me in a ditch.

Alas, I survived but my point still stands.
Profile Image for Brooke ♡.
305 reviews39 followers
February 1, 2024
3/5 stars!

Thank you so much for the ARC!!!

This is technically the first manga I've actually cracked open to read, and it did not disappoint! This gave strong heartstopper vibes and i really enjoyed it. I wish it was a lil longer though, and maybe had some more 'time' information throughout (it was a lil hard to differentiate the memories/younger them when in flashbacks vs. them now– kinda was jarring when it all of a sudden would be them when they were younger randomly in the middle of them talking in the future lol if this makes sense)

However i thought this was a light cute lil read and was a graphic novel/manga, which i don't read often!! I may need to pick up a few more though :D.
Profile Image for Leila.
499 reviews9 followers
April 26, 2022
3.5☆
Il fumetto non si spinge oltre a quello che dice la trama: tratta solo di questo sentimento non espresso, non approfondisce altro. Gli altri due amici dei protagonisti fanno solo da contorno, non vengono mai presentati. Gli sfondi mancano quasi del tutto. Ma quindi questo manga merita? Se cercate qualcosa di veramente molto leggero e malinconico, questo fa al caso vostro; perché se è vero che non tratta di altro, quello che viene presentato lo fa bene secondo me. Mi ha un po' smosso. È stata una lettura piacevole. Lo rileggerei volentieri.
Profile Image for Haku.
27 reviews4 followers
January 3, 2025
This book put me through a lot of emotions while reading it. I felt so bad for Kai since I know what it is like to feel closeted about your sexuality. This book was a slow burn so I would recommend it if you are into slow burn books. Overall this is a good book to start out the year with and I am excited to read more of Nagisa Furuya's work.

"You're the one who's made my teenage year worthwhile, my ultramarine sky."
Profile Image for Fny.
649 reviews17 followers
January 15, 2024
I mean my heart melted … such an adorable innocent bl… it warmed my heart so much.

Plot wise nothing revolutionary but I like this mangaka a lot. Her art style is so cozy…. & sometime I need something like this…low angst and just sweet…,
Profile Image for Afra.
238 reviews12 followers
January 6, 2024
Thank you Netgalley and Publisher for this advanced copy.

A sweet tender love story. I loved how this manga had 2 POV, so we could understand the 2 main characters better. LOVE IT.
Profile Image for Bee.
77 reviews
January 26, 2024
Thank you to NetGalley and the publisher for sending me an advanced copy in exchange for a fair and honest review!

I loved this manga, a sweet a beautiful exploration of two long time friends dealing with the woes of not knowing if your friend could ever be in love with you back. An absolute delight of a single volume story. The art is lovely and captures the teenage awkwardness that helps carry the other emotions. Would absolutely recomend for anyone looking for a low stakes happy ending YA style BL manga.
Profile Image for hanni.
50 reviews28 followers
January 14, 2025
3.5★ This was a sweet and solid childhood friends to lovers boys love, and I enjoyed the characters and calmness a lot, despite the story having its limitations (like most one shots do).

The plot and the way their relationship developed were mostly predictable but for what it was, it managed to do it well. I especially liked the golden retriever and black cat dynamic between the main characters, and the flashbacks which did a great job at helping understand how their friendship started and evolved into more while growing up. The mangaka also just knows how to deliver a calm, melancholic atmosphere and the characters’ emotions through their art.

Overall, I was missing a little something for it to really catch me but it was cute nonetheless and I would definitely recommend reading. The bonus chapter at the end was super adorable though and gave me exactly what I needed - the couple just enjoying their time together after overcoming their hardships.

Thank you to Netgalley and Kodansha Comics for providing me a free copy in exchange for an honest review!
Profile Image for Mayu.
1,290 reviews163 followers
May 18, 2018
Los protagonistas son compañeros de clase que empiezan a gustarse pero como no se atreven a confesarse por miedo permanecen en la friendzone.

####

Apenas recuerdo nada de este manga, y creo que es porque lo odié muchísimo. Me decepcionó y cabreó tanto que juré no volver a leer a la autora y la verdad es que lo mantengo.

Yo odio las historias lentas, que hacen de su base y desarrollo todo un malentendido. Me parece que los protagonistas desperdiciaron el tiempo juntos por sus tontos miedos. Se hacian daño por no contarse lo que sentían, y odio eso porque lo veo gratuito y tonto, y realmente hace ver que no eran tan amigos.

No recuerdo nada más de la historia. Solo que ambos me parecieron insoportables, tan idiotas, y acabé harta de ellos.
Profile Image for reese ♡.
81 reviews13 followers
May 31, 2020
3.5 stars.

It was a fun and cute read about inseparable childhood friends finding love in and with each other. Would definitely read again because I really loved the main protagonists and their friend group.
Profile Image for James Cooper.
333 reviews17 followers
January 16, 2024
Thank you to NetGalley and Kondasha publishers for accepting me as pre-publication reviewer of the English translation of this manga.

This follows Kai and Ren who have been in the same class all through middle and most of high school but are separated in their final year. From this, Kai feels they’re growing apart and whilst Ren is asleep decides to tell him his love may not be wholly platonic. But will this be reciprocated?

I loved how this manga goes along, the two MCs were great, rather complex and we also get introduced to their friends which was nice. The flashback moments to Ren and Kai’s past were very nice and definitely added to the current plot line. The artwork is very cute and so’s the story as a whole but I didn’t like how a lot of times characters are drawn with only one eye, like I just couldn’t take my eye off it (I didn’t mean to do that) and just felt it was strange. The dual POV aspect was nice which allows the reader to understand both of these characters in more depth. I think this would have been better as a series maybe as I was left pining for more and felt it was too short for all the development I wished for. I also really appreciated this manga not containing any explicit scenes which is so common in BLs, containing fluff but it’s not loads with most of the story being grounded in the character studies and their relationship.

Overall, I did enjoy this a lot and would recommend it. It’s not a favourite but has made me want to check out more of Nagisa Furuya’s works.
Profile Image for Bee.
77 reviews
January 5, 2024
4.5 stars

Listen I absolutely loved this manga. And I would've given it 5 stars but I felt like Ren's realization of being in love with Kai was a tad rushed. They didn't get together until the very end and even then when Ren confessed he still had a girlfriend. Also this is not the mangaka's fault but this manga originally came out in 2015 and just got translated in 2023!!! What?!?! Why did it take nearly 10yrs!!

Other than those small little things I really enjoyed this manga. It did not disappoint! I loved all the characters and the plotline for the most part. I also really loved the slow burn and build for the characters it was just so good. I lost it when Kai found out Ren knew about his feelings. Especially because Kai sat there and said "You know... I knew I never should have fallen for you." LIKE SHUT UP RIGHT NOW YOU DON'T MEAN THAT. Ren's confession was also sooo good. But yes I loved this manga. I've said it before and I'll say it again, I absolutely love this mangaka's art and storylines so freaking much. I hope to continue reading more of their work.
This entire review has been hidden because of spoilers.
Profile Image for H.
39 reviews11 followers
January 8, 2024
I am never gonna look away from a friends to lovers trope. I think it’s a sweet trope that can be done in a lot of ways. My Ultramarine Sky went more for the classic route but it was still enjoyable.

Kai and Ren are the typical gooses you just want to shake a bit so they’ll actually communicate. I do love miscommunication and it didn’t feel drawn out in this volume. Also, angst did appear for a second and I also do love a good angst moment.

My only problem was the dialogue fell flat at some moments and I didn’t feel fully drawn in like I have with other friends to lovers storyline. Overall, it was a sweet manga and the world can never have too many cute mangas.
Profile Image for Drakoulis.
336 reviews32 followers
February 6, 2024
A pleasant, quick read with a simple story of boys discovering their feelings.

I wasn't exactly blown away by it, but I will give a shot to the author's most known comic in the future nonetheless.

Thank you NetGalley and Kodansha Comics for the ARC!
Profile Image for Devon Rose.
688 reviews34 followers
April 18, 2024
This one shot was very cute, a little more angst than the other one I read by this author and I liked how the side characters had more personality! Definitely a fluffy, sweet BL for days when you just need a pick me up.
Profile Image for Lucca Ángel.
130 reviews4 followers
November 4, 2024
3.5*

I liked this a lot more than Summer of You! Sadly, it was too fast-paced and doesn’t rly give the reader time to sit with the characters :( cute for what it is, but I would have loved for this to be longer and show more conflict!
Profile Image for Daniel.
1,023 reviews91 followers
February 12, 2024
Another pair of high school boys falling in love. G-rated. Standalone volume.

Nothing particularly original here, but I really like Nagisa Furuya's stuff for some reason.
Profile Image for Pamela.
87 reviews217 followers
February 6, 2024
I would like to thank NetGalley, Nagisa Furuya and Kodansha Comics for an ARC copy of this book in exchange for my honest review

3 ⭐ - this was such a cute and sweet friends to lovers story. This was also my first time ever reading a manga. New year, new reading goals? 😂

Anyway the story did not disappoint and I might try reading some other manga.
Displaying 1 - 30 of 334 reviews

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