Series synopsis
ONIMAI: I'm Now Your Sister!, also known as お兄ちゃんはおしまい！ is a Japanese animation comedy television series that premiered on AT-X on January 5, 2023. It ended on March 23, 2023. It stars Marika Kouno, Kaori Ishihara, Hisako Kanemoto and Minami Tsuda.
When lazy, erotic-game loving Mahiro Oyama is transformed into a girl by his younger scientist sister's experiments, he becomes determined to change back, only to recognize that with his new opportunity, he may want to turn his life around.
Premise
When lazy, erotic-game loving Mahiro Oyama is transformed into a girl by his younger scientist sister's experiments, he becomes determined to change back, only to recognize that with his new opportunity, he may want to turn his life around.
Cast and characters
Leading cast
- Marika Kouno as Mahiro Oyama (voice)
- Kaori Ishihara as Mihari Oyama (voice)
- Hisako Kanemoto as Kaede Hozuki (voice)
- Minami Tsuda as Momiji Hozuki (voice)
- Kana Yuuki as Asahi Ohka (voice)
- Natsumi Hioka as Miyo Murosaki (voice)
Guest cast
- Hiroaki Miura as Seme (voice)
- Hisayoshi Suganuma as Uke (voice)
- Reimi as Child - Brother (voice)
- Emiri Suyama as Woman A (voice)
- Yuuya Uchida as Leonardo (voice)
- Hironari Nemoto as Movie Narration (voice)
- Erisa Kuon as Woman B (voice)
- Kousuke Goto as Spabone (voice)
- Enako as Nicolala (voice)
- Yoshie Saito as Tomoya Kiba (voice)
- Yuri Ise as Student A (voice)
- Ren Arata as Student B (voice)
Episodes
This series spans 1 season with 12 episodes.
| Season | Episodes | First aired | Last aired |
|---|---|---|---|
| Season 1 | 12 | January 5, 2023 | March 23, 2023 |
| Episode | Title | Air date |
|---|---|---|
| 1 |
Mahiro's Confusing New Body We follow Mahiro Oyama, an unemployed good-for-nothing shut-in, who not only hasn't left the house in two years, but is also exceedingly addicted to gross video games. One afternoon, he wakes up and notices that his body feels a little off. Finding that strange, he goes to reach for his tablet, but what does he see in his reflection, but an adorable young lady. I wonder what lies in store for the "former" big brother, Mahiro as he's thrust headfirst into his new life as a girl. |
January 5, 2023 |
| 2 |
Mahiro's Time of the Month As Mahiro stumbles through his new life as a girl, he finds himself gradually beginning to get into the swing of things. Realizing this, however, prompts him to try and reclaim some of his masculinity. He tries, in futility, to engage his core and do a sit-up, but ends up with a stomachache instead. Seeing his condition worsen rapidly before her eyes, Mihari has an epiphany. She realizes that his pain may actually have something to do with fact that almost a month has passed since Mahiro turned into a girl... |
January 12, 2023 |
| 3 |
Mahiro's Close Encounter Mahiro makes a mad dash for the bathroom, but when he opens the door, he finds the facilities are already occupied by a high school girl he's never met. This bold fashionista turns out to be Kaede, Mihari's old classmate from middle school. Mahiro is initially a little nervous around her, but as he gets to know her, he learns how much of a nice person she is and becomes quite attached to her. Then, out of nowhere, Kaede asks "You've never done it before, have you?" and begins to scooch closer to a puzzled Mahiro. I wonder what she's about to do next... |
January 19, 2023 |
Production
Release
| Original network/platform | AT-X |
|---|---|
| First aired | January 5, 2023 |
| Last aired | March 23, 2023 |
| Runtime | 24 minutes |
| Status | ended |
| Schedule | Thursday |