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魔王城でおやすみ [Maō-jō de Oyasumi] #12

Sleepy Princess in the Demon Castle, Vol. 12

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Kidnapped by the Demon King and imprisoned in his castle, Princess Syalis is…bored.

The Demon Castle staff procure a flock of Monster Bird chicks to ensure a steady supply of eggs, but their problems only grow. The princess’s efforts to help the Demon Castle weather a financial crisis range from the criminal to the musical. Mechanical Zone boss MOTHER creates a mechanical marvel modeled after the most fearsome resident of the castle. Now who would that be…? And then the princess must operate the mecha in battle against the hero Dawner, who is determined to "rescue" her from her beloved new home. Plus, the secret of the Demon King’s horns and an herbaceous invasion!

168 pages, Paperback

First published September 18, 2019

19 people are currently reading
85 people want to read

About the author

Kagiji Kumanomata

41 books28 followers

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5 stars
91 (54%)
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57 (33%)
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Displaying 1 - 14 of 14 reviews
Profile Image for Jillian -always aspiring-.
1,870 reviews535 followers
July 1, 2020
2020 Read #474

Prior to this volume, I was all Syalis/Demon Cleric, but now...I actually want Syalis/Poseidon???? What goes on here?! (Also, I laughed uncontrollably for a few minutes at the scene where the demons freaked out when they thought Syalis had a lover in her cell. Good times.)
Profile Image for haven ⋄ f (hiatus).
803 reviews15 followers
May 12, 2020
This is one of the funniest manga I have read!

I've loved the older volumes and this one was no exception. Most of the volumes didn't seem to have an overarching story, but as you read farther and farther in, you begin to realize that there's an overall story and not just individual stories. These stories were full of humor that were all on point. Most of the humor comes from misunderstandings that the princess (typically) makes. The characters are fabulous and well designed. I really like the art style too. You can tell the author spent a lot of time on this.

Thanks to the publisher and netgalley for providing the arc for a review!
Profile Image for Abi.
2,277 reviews
June 13, 2020
This is such a fun series, and this volume was no exception. It continues the funny misunderstandings and character interactions from previous volumes, and introduces a new character. It was light, entertaining, and all around enjoyable. I'd definitely recommend the series! 4.5 stars.
Profile Image for Nadina.
3,194 reviews5 followers
April 4, 2024
I love Syalis, this was an awesome volume and it was a lot of fun. I loved Twilight in this volume, and really enjoyed the connection that Syalis and Twilight had in this, both being royalty.
Another cute volume in a cute series. I look forward to the next one.
1,797 reviews
Read
January 4, 2022
I found this volume particularly amusing. The interactions with Poseidon and her “battle” with the hero were hilarious. I also enjoyed the chapter with demon mint - as someone that is always trying to eradicate ivy and such, i totally sympathized with the demons
Profile Image for Claire.
3,440 reviews45 followers
August 26, 2023
This volume is so good! The robot version of the princess, the horns, the confusion with Poseidon. Really love this series.
443 reviews2 followers
May 16, 2025
I will never not love this series; five stars as usual 🥰
Profile Image for Emma (littledollreads).
1,045 reviews25 followers
September 6, 2023
Well hello M.O.T.H.E.R. you have officially become one of my favorite characters in this series. Apart from all of the awesomeness that he has now brought to the series I love the relationship that exists between the king and the princess because sometimes they are having a touching heart to heart and the next she is causing him extreme anguish while inadvertently doing him enormous favors, it's great.

Reread:
- The cursed musician is most decidedly overworked, he has too many jobs and is thus most susceptible to absolutely random nonsensical tasks put upon him by the council and the princess
- Sometimes the princess really needs to just not meddle in other people's affairs
- I imagine the princess has no sense of privacy because she is a princess, when we did that bath story we saw here with like 20 maids in there
- There are a shocking amount of plots devoted to the financial stability of the Demon castle
- The idol arc that no one knew they needed
- Once again a brief moment of genuine goodness from the princess, solving the problem she created in a less than disastrous manner, sort of
- Fun fact, the demon king's horns grow back. Actually shocked his friends didn't know that
- The princess most definitely could use a primer on privacy, I really don’t think she knows how to be private
- MOTHER really should see the doctor, Last time I checked it was the cursed musician and he is not paid enough to go against one of the 10 guardians
- Buff Poseidon is arguable better than regular Poseidon, he looks more like his brother this way
- Princess + MOTHER+ Scissor Sorceror + Teddy Demon +grimoir = Demon mint eradicators
Profile Image for Marianne.
591 reviews15 followers
October 19, 2021
Laughter upon laughter upon laughter!! It just never stops 🤣📖. All the shenanigans that Syalis and her friends though of here made me laughing out loud! Was surprised at some chapters, and sometimes, I just simply lost it. It's that hilarious 📖🤣
Profile Image for Mara.
1,054 reviews4 followers
January 7, 2026
The cutest series I've ever read.
Displaying 1 - 14 of 14 reviews

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