# ONIMAI: I'm Now Your Sister! (2023)

> A lazy otaku is turned into a girl by his scientist sister and must navigate junior high life while deciding whether he really wants to change back.

Canonical page: https://ember.film/tv/123886

## Facts

- Seasons: 1
- Episodes: 12
- Episode runtime: 24 min
- Status: Ended
- Genres: animation, comedy
- Network: AT-X
- Cast: Marika Kouno, Kaori Ishihara, Hisako Kanemoto, Minami Tsuda, Kana Yuuki, Natsumi Hioka, Hiroaki Miura, Hisayoshi Suganuma
- TMDB rating: 6.7/10
- IMDb: https://www.imdb.com/title/tt21929424/

## Ember's analysis

- Pacing: brisk
- Intensity: mild
- Complexity: simple
- Violence: none
- Tone: flustered, playful, lighthearted, comforting, absurd

## What critics say

Audience reception is mixed, with a modest audience rating for this single-season gender-swap comedy.

## Synopsis

ONIMAI: I'm Now Your Sister! (2023) is a Japanese anime comedy series produced by Studio Bind and EGG FIRM, broadcast on AT-X, and based on a manga. Its single 12-episode season follows Mahiro Oyama (voiced by Marika Kouno), a lazy young man devoted to erotic video games, who is transformed into a girl by the experiments of his younger scientist sister Mihari Oyama (voiced by Kaori Ishihara). Mahiro's goal is to change back, but the new life at a junior high school among classmates such as Kaede Hozuki (voiced by Hisako Kanemoto) and Momiji Hozuki (voiced by Minami Tsuda) pulls him toward a different question: whether he might use this strange opportunity to turn his life around. Each episode is a self-contained run of school life mishaps, embarrassing situations, and awkward encounters, built on the gender swap premise. The mood is light and flustered, with frequent fan-service tones, playful sibling bickering, and gentle slice of life warmth. Fans of Ranma ½ and Monthly Girls' Nozaki-kun will find resonance in its gender-bending comedy and school-set romantic chaos, while those who enjoy absurd high-concept anime comedies will recognize its lighthearted spirit throughout.

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