Maoujou de Oyasumi

Sleepy Princess in the Demon Castle

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Alternative Titles

English: Sleepy Princess in the Demon Castle
Synonyms: Sleeping in Devil's Castle
Japanese: 魔王城でおやすみ


Type: TV
Episodes: 12
Status: Finished Airing
Aired: Oct 6, 2020 to Dec 22, 2020
Premiered: Fall 2020
Broadcast: Tuesdays at 02:00 (JST)
Producers: Lantis
Licensors: Funimation
Studios: Doga Kobo
Source: Manga
Genres: ComedyComedy, FantasyFantasy
Theme: DemonsDemons
Demographic: ShounenShounen
Duration: 23 min. per ep.
Rating: PG-13 - Teens 13 or older


Score: 8.011 (scored by 6301663,016 users)
1 indicates a weighted score.
Ranked: #5492
2 based on the top anime page. Please note that 'Not yet aired' and 'R18+' titles are excluded.
Popularity: #1210
Members: 146,386
Favorites: 1,527

External Links

Ranked #549Popularity #1210Members 146,386
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The Demon Lord Tasogare's castle is a dark and frightening place, filled to the brim with various monsters. Any soul unfortunate enough to be imprisoned here is sure to be terrified by the horrors within. However, the human princess Aurora Suya Rhys "Syalis" Kaymin is a different case. Rather indifferent to her situation, Syalis worries about one thing and one thing only—sleep. Ever since the demon lord kidnapped her from her kingdom, she has not had a single good night's rest.

To alleviate her dozen dozing issues, the princess makes do with what she can find in the castle. Whether it be the fur of fluffy demonic teddy bears or the silky, blanket-like bodies of ghost shrouds, everything is but a means to ensure a peaceful slumber. With so many potential materials to craft items that can help her sleep at her disposal, nothing will stop the sleepy princess—not even death.

[Written by MAL Rewrite]


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Related Anime

Characters & Voice Actors


Yamazaki, Mitsue
Shirahata, Yoshiyuki
Episode Director
Minase, Inori
Theme Song Performance
Theme Song Performance


Opening Theme

Apple Music
Amazon Music
Youtube Music
"Kaimin! Anmin! Suya Rhyst Seikatsu (快眠!安眠!スヤリスト生活)" by Aurora Suya Rhys Kaymin (Inori Minase)

Ending Theme

"Gimmme!" by ORESAMA

Dec 22, 2020
Cocoa_Hoto (All reviews)
'If you got kidnapped and imprisoned by the demons, what should you do?'

Well obviously in this situation, you will always try to find a way to escape from their prisoner. But for this anime, Princess Syalis is the most unique one. She rather sleeps in her prison bed despite the panicking situation that is happening in her homeland.

But there's one problem! The demons only give her nothing but a low quality bed sheet and pillow. Dissatisfied, Hime-sama decides to go out and create the best quality for her to sleep even if it means murdering demons and destroying useful items. What makes the story even read more
Dec 21, 2020
dlxuniuniu (All reviews)
(Quiet please, our princess is sleeping right now)

How far would you go for THE perfect sleep? It has been scientifically proven that a good sleep is very important for our body, but how can we achieve that? This is the most important thought of our princess Aurora Suya Rhys (or let's just say Suyaaaaa~), she goes all out to get this achievement.

In a time when humans and demons were still hostile, our princess was captured by the demon king Tasogare. He locked her up and just gave her an old mattress and sheet to sleep on. How is our princess supposed to have a restful read more
Dec 21, 2020
Watame (All reviews)
‘I love sleep. My life has the tendency to fall apart when I am awake, you know?’

Once upon a time, people lived happily in the kingdom of Sleepland. A jealous demon king appeared, wishing to destroy the kingdom. He kidnapped the princess and said, ‘I am kidnapping your Princess and if she is dear to you, you will give all your lands to the demons.’ So, just like in any typical fairy tale: an evil and insidious demon king, in order to show these mongrels, who are called humans, who the real king is, kidnaps a young maiden and imprisons her in a cell in read more
Dec 21, 2020
Stark700 (All reviews)
As humans, we all have three necessities in life: breathe, eat, and sleep. If you go extended amount of time without any of these three, then death will await you at open doors. However, sleep is a more subjective and everyone gets different amounts. What about the princess of the human kingdom though? How much sleep does Syalis need every day in her life?

Those coming into a magical-fantasy story like this should keep your expectations in check. This isn’t some complex tale crafted with deep lore or character study. If it can even be called that, Syalis is a princess that wants nothing more than read more

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