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魔王城でおやすみ [Maō-jō de Oyasumi] #10
Sleepy Princess in the Demon Castle, Vol. 10
A captured princess just wants a good night’s sleep! Shhh…
Kidnapped by the Demon King and imprisoned in his castle, Princess Syalis is…bored.
Princess Syalis refuses to play the part of the damsel in distress in a video begging Dawner, the bumbling knight in hining armor, to rescue her. Instead, she wants to be an armchair detective, a D.I.Y. hairdresser, and best friend to all hings furry. But she is mistaken for Poseidon’s girlfriend, an assassin, and most shockingly of all, Demon King Twilight’s wife. How will Midnight (Twilight’s father and the former demon king) take to his son’s wife—er, hostage princess? And will the temperamental, dangerous old demon approve of the way his son is running the kingdom...?
Kidnapped by the Demon King and imprisoned in his castle, Princess Syalis is…bored.
Princess Syalis refuses to play the part of the damsel in distress in a video begging Dawner, the bumbling knight in hining armor, to rescue her. Instead, she wants to be an armchair detective, a D.I.Y. hairdresser, and best friend to all hings furry. But she is mistaken for Poseidon’s girlfriend, an assassin, and most shockingly of all, Demon King Twilight’s wife. How will Midnight (Twilight’s father and the former demon king) take to his son’s wife—er, hostage princess? And will the temperamental, dangerous old demon approve of the way his son is running the kingdom...?
168 pages, Paperback
First published February 18, 2019
21 people are currently reading
90 people want to read
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Displaying 1 - 12 of 12 reviews
December 10, 2019
This was a really fun installment in the series, and I was definitely looking forward to it. It didn't disappoint! I loved seeing all the hijinks that the characters got up to, like meeting King Midnight. It was very enjoyable, and I look forward to the next volume. 4.5 stars!
October 19, 2021
This one has some serious undertones in it. But I like the fact that it still maintains its hilarity despite the seriousness of some of the chapters. Awesome volume that always puts me into chuckles and laughter. 😁📖
December 4, 2019
Ten volumes now, and things are starting to feel a bit redundant... Even so, I still want to see where this cast of characters goes.
July 12, 2020
Funny as always. It’s always a treat to see someone else’s perspective of the princess. Love their field trips.
So many misunderstandings. It’s crazy. I wonder how long it’s gonna go.
So many misunderstandings. It’s crazy. I wonder how long it’s gonna go.
April 23, 2025
Full of misunderstandings and bad haircuts, volume 10 did not disappoint!
October 5, 2020
Sleepy Princess in the Demon Castle volume 10 immediately became great once it suddenly became extremely Conan heavy.
But of course, there’s more to Syalis and the demons than that! How about when they all venture to a spot to shoot a film, only that they didn’t tell the princess this excursion would happen, and full revolt ensued at said location? Or when Syalis cut her bangs so poorly that everyone in the demon castle that saw her at the cafeteria didn’t point it out…except the one who wasn’t there, Demon Cleric. Poor guy wishes he could become a gentleman. And then, everyone is up in arms when it appears Poseidon and the Princess are…in love?!? How bad do they feel when they discover that’s not the case? You’ll have to read to find out!
However, this volume introduces us to the former Demon King — A.K.A., the current Demon King’s pops. The current Demon Castle needs some restoration, so the demons aim to ask him to help restore it…and make sure Syalis doesn’t find out. You nod as you understand she does of course find out — despite them going into almost meticulous levels of detail to make sure she didn’t! But, in a twist, they end up lying to the former Demon King and say she’s a demon in his presence. How will this particularly spectacular lie go over with the old man?
Well, once he sees her in her hostage clothing and act like the torture’s taken its toll, he can only get the wrong idea. And that wrong idea almost gets the current Demon King and his lackeys killed. This is a good sign that maybe the current Demon King needs to shed being single…
Outside of that long arc, which even has the former Demon King travel to the Demon Castle and see Syalis desecrate the castle’s horns, this is yet another hilarious volume. I was not kidding when I mentioned it brings out Detective Conan references — there’s one chapter where, for one of the few times in this series, Syalis falls asleep early. She’s supposed to be cracking mysteries, but instead, the Demon King (no Voice-Changing Bowtie though) solves the very trivial cases for her! There’s another chapter where a character that’s a huge reminder of Amuro shows up and was real close to messing himself up because he’s thinking Syalis is really gonna mess the Demon King up.
More inspirations and riffs on common elements in games occur, whether it’s because she dies, gets resurrected, and starts abusing inanimate objects (this also includes her making the demons believe she’s proposing to them, when in reality she’s trying to have servants), and it never fails to spark so much laughter. Between that, the continuously appealing art style and the variety of stories makes this one too good once again. Another successful volume where we continue to follow Syalis’ helpful and totally normal sleeping adventures!
- Justin
But of course, there’s more to Syalis and the demons than that! How about when they all venture to a spot to shoot a film, only that they didn’t tell the princess this excursion would happen, and full revolt ensued at said location? Or when Syalis cut her bangs so poorly that everyone in the demon castle that saw her at the cafeteria didn’t point it out…except the one who wasn’t there, Demon Cleric. Poor guy wishes he could become a gentleman. And then, everyone is up in arms when it appears Poseidon and the Princess are…in love?!? How bad do they feel when they discover that’s not the case? You’ll have to read to find out!
However, this volume introduces us to the former Demon King — A.K.A., the current Demon King’s pops. The current Demon Castle needs some restoration, so the demons aim to ask him to help restore it…and make sure Syalis doesn’t find out. You nod as you understand she does of course find out — despite them going into almost meticulous levels of detail to make sure she didn’t! But, in a twist, they end up lying to the former Demon King and say she’s a demon in his presence. How will this particularly spectacular lie go over with the old man?
Well, once he sees her in her hostage clothing and act like the torture’s taken its toll, he can only get the wrong idea. And that wrong idea almost gets the current Demon King and his lackeys killed. This is a good sign that maybe the current Demon King needs to shed being single…
Outside of that long arc, which even has the former Demon King travel to the Demon Castle and see Syalis desecrate the castle’s horns, this is yet another hilarious volume. I was not kidding when I mentioned it brings out Detective Conan references — there’s one chapter where, for one of the few times in this series, Syalis falls asleep early. She’s supposed to be cracking mysteries, but instead, the Demon King (no Voice-Changing Bowtie though) solves the very trivial cases for her! There’s another chapter where a character that’s a huge reminder of Amuro shows up and was real close to messing himself up because he’s thinking Syalis is really gonna mess the Demon King up.
More inspirations and riffs on common elements in games occur, whether it’s because she dies, gets resurrected, and starts abusing inanimate objects (this also includes her making the demons believe she’s proposing to them, when in reality she’s trying to have servants), and it never fails to spark so much laughter. Between that, the continuously appealing art style and the variety of stories makes this one too good once again. Another successful volume where we continue to follow Syalis’ helpful and totally normal sleeping adventures!
- Justin
June 16, 2024
It amazes me how the author continues making new scenarios based on this premise. Ten volumes and they're still making me laugh.
Grimorie being out of the loop
Sleeping Sylasis the detective.
The motivational hostage video.
I laughed my way through this.
The egg-plant seal misunderstanding reminded that this series, as cute and silly as it is, is totally aimed at adults. That whole chapter would go over a kid's head.
Grimorie being out of the loop
Sleeping Sylasis the detective.
The motivational hostage video.
I laughed my way through this.
The egg-plant seal misunderstanding reminded that this series, as cute and silly as it is, is totally aimed at adults. That whole chapter would go over a kid's head.
December 22, 2022
I read all the chapter but it only shows it in volume form
August 17, 2023
Syalis and Great Red having vacation time is hilarious. Twilight's dad is a scream. So many crossed wires in this book. Maybe she is a demon.
September 4, 2023
4.5*
Oh my god the poor demon king, he just can't catch a break. The story here continues to move slowly forward in ways but this volume mostly felt like more holding pattern but that is ok because it is super hilarious. I like that we have now met both parents of the princess and the king and family just makes their interactions so much funnier. I also still love how the princess keeps getting herself into sort of romantic situations without realizing it, I think she did it about three times here. The poor daemons are so thrown every time this happens. I also found it interesting how acclimatized she has become to the demons to the point where other demons think that she herself is one.
reread:
- I am so shocked the grimoire hasn’t experienced any of the princess's destructive tendencies
- Yes Twilight, the princess while asleep does actually display some of the fairer qualities of a princess, you fule those shipping fires
- Occasionally Twilight is able to utalize the princesses chaoticness to his benefit
- The sheer amount of poorly phrased things said by these people and the absurd conclusions the others jump too is just peak
- The perception the princess has of these demons is just so too their cores that they don’t even realize it
- Former Demon King Midnight is so big
- See, even Midnight thinks they are a matching pair
- The frequency which the demon think that the princess is proposing or offering a declaration of love is staggering. They should really know better by now that she has no idea about any of that and if she did I’m sure she would be in her serious mode for it not her normal sleepy silly mode
Oh my god the poor demon king, he just can't catch a break. The story here continues to move slowly forward in ways but this volume mostly felt like more holding pattern but that is ok because it is super hilarious. I like that we have now met both parents of the princess and the king and family just makes their interactions so much funnier. I also still love how the princess keeps getting herself into sort of romantic situations without realizing it, I think she did it about three times here. The poor daemons are so thrown every time this happens. I also found it interesting how acclimatized she has become to the demons to the point where other demons think that she herself is one.
reread:
- I am so shocked the grimoire hasn’t experienced any of the princess's destructive tendencies
- Yes Twilight, the princess while asleep does actually display some of the fairer qualities of a princess, you fule those shipping fires
- Occasionally Twilight is able to utalize the princesses chaoticness to his benefit
- The sheer amount of poorly phrased things said by these people and the absurd conclusions the others jump too is just peak
- The perception the princess has of these demons is just so too their cores that they don’t even realize it
- Former Demon King Midnight is so big
- See, even Midnight thinks they are a matching pair
- The frequency which the demon think that the princess is proposing or offering a declaration of love is staggering. They should really know better by now that she has no idea about any of that and if she did I’m sure she would be in her serious mode for it not her normal sleepy silly mode
April 3, 2024
At this point in a series I find it hard to give a detailed review.
The quality of the story and the manga as a whole continues to be good and the story continues to be enjoyable. I look forward to the next volume.
For more detailed reviews of the series see the early volumes (as well as, once I finish the series, the final volume).
The quality of the story and the manga as a whole continues to be good and the story continues to be enjoyable. I look forward to the next volume.
For more detailed reviews of the series see the early volumes (as well as, once I finish the series, the final volume).
January 7, 2026
The cutest series I've ever read.
Displaying 1 - 12 of 12 reviews