ONIMAI: I’m Now Your Sister! premieres next month


ONIMAI: I’m Now Your Sister! will premiere on January 5 as part of the Winter 2023 anime season.

ONIMAI is a light-hearted comedy series that follows Mahiro Oyama, an otaku who lives with his mad scientist younger sister Mihari. As part of an experiment (i.e. prank), Mahiro’s sister turns him into a young girl and refuses to change him back!

ONIMAI: I’m Now Your Sister! will be the second series from Studio Bind, a relatively new studio founded in 2018 who made a name for themselves with their first anime production: Mushoku Tensei: Jobless Reincarnation. You can check out the latest trailer here.

The series began in 2017 and is serialized in Monthly Comic Rex in Japan under the title Onii-chan wa Oshimai! (Onii-chan is Done For!).

You can read a summary of the series from MyAnimeList below.

Mahiro Oyama was just a normal erotic-game loving dude…until he woke up one morning as a woman! Turns out his mad-scientist little sister, Mihari, tried out one of her new experiments on him… with a disastrous outcome, as far as Mahiro’s concerned! But Mihari is as determined to study him as he is determined to go back to his shut-in, game-playing life, and one thing’s for sure… life is going to get a whole lot weirder from here on out!

The manga is published in English by Kodansha USA.



A basement-dwelling ogre, Brandon's a fan of indie games and slice of life anime. Has too many games and not enough time.

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