ONIMAI: I'm Now Your Sister! - Season 1 - Eps 9: Mahiro Rings in the New Year
It's Christmas and Mahiro is shocked to hear his own little sister has a date. Unable to shake his unease, he follows her through the festive hustle and bustle in secret, with Momiji as his escort in tow. Who could Mihari possibly be meeting with?
About ONIMAI: I'm Now Your Sister!

Title: ONIMAI: I'm Now Your Sister!
First Air Date: 2023-01-05
Last Air Date: 2023-03-23
Status: Ended
Rating: 7.4/10 (from 42 votes)
Language: JA
Seasons: 1
Total Episodes: 12
Network: AT-X
Genres: Animation, Comedy
Production Companies: Studio Bind, EGG FIRM, Ichijinsha, TOHO, Hakuhodo DY Music & Pictures, AT-X, BS11, PIA Corporation, Pony Canyon, movic, Tokyo MX, Bit grooove promotion
Synopsis
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

Marika Kouno
Mahiro Oyama (voice)

Kaori Ishihara
Mihari Oyama (voice)

Hisako Kanemoto
Kaede Hozuki (voice)

Minami Tsuda
Momiji Hozuki (voice)

Kana Yuuki
Asahi Ohka (voice)

Natsumi Hioka
Miyo Murosaki (voice)