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Anime series

ONIMAI: I'm Now Your Sister!

Latest episode

S1 E12 · Mahiro's Future as a Sister

About ONIMAI: I'm Now Your Sister!

ONIMAI: I'm Now Your Sister! is a comedy anime series that premiered on AT-X on January 5, 2023. It has 1 season and 12 episodes so far and has ended. The latest episode, Season 1 Episode 12 "Mahiro's Future as a Sister", aired on March 23, 2023.

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.

  • Comedy
  • Animation

Last updated

Episodes

12 episodes · 1 season

Season 1

2023 · 12 episodes · Last episode: 3 years ago

ONIMAI: I'm Now Your Sister! Season 1 release dates →
  1. ONIMAI: I'm Now Your Sister! S1 E12 still E12

    12. Mahiro's Future as a Sister

    Mahiro and the girls take a trip to a Japanese inn over spring break. First they hit the town in their yukata, before heading to the open-air bath to detox. However, things go south when Mahiro begins to feel a familar tingling sensation between his legs.

  2. ONIMAI: I'm Now Your Sister! S1 E11 still E11

    11. Mahiro Pretties Up

    Horoscopes are all the rage at school right now, and Mahiro is curious to see what all the fuss about. According to his forecast, an important occasion is on the horizon and he may be in for a surprise or two. But what occasion could it be alluding to?

  3. ONIMAI: I'm Now Your Sister! S1 E10 still E10

    10. Mahiro Ponders Boobs and Identity

    It's the start of the third semester and winter uniforms are now in effect. For Mahiro and the girls at school, this means braving the cold winter air in mandatory skirts. Who knows how Miyo will react when he and Momiji show up in matching scarves, too.

  4. ONIMAI: I'm Now Your Sister! S1 E9 still E9

    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?

  5. ONIMAI: I'm Now Your Sister! S1 E8 still E8

    8. Mahiro's First Girls Sleepover

    It's finally winter break and Mahiro is excited to get into his Winter Vacation Mode. Unbeknownst to him, however, Mihari invites Momiji and the others over for a sleepover. She hopes this will prevent a potential relapse into his old, shut-in ways.

  6. ONIMAI: I'm Now Your Sister! S1 E7 still E7

    7. Mahiro's Role-Playing Game

    Just when Mahiro is beginning to get used to middle school life again, finals are upon them. Despite his initial blasé attitude, Mahiro finds himself reluctantly handing in a 80% blank answer sheet after having slept through the entire first exam.

  7. ONIMAI: I'm Now Your Sister! S1 E6 still E6

    6. Mahiro Goes Back to Middle School

    Momiji shows up at Mahiro's house with her two classmates, Asahi Ohka and Miyo Murosaki, to invite him out for parfaits.

  8. ONIMAI: I'm Now Your Sister! S1 E5 still E5

    5. Mahiro Discovers Adventure and Social Gatherings

    In a rare turn of events, Mihari wakes up one morning to find Mahiro has gotten up before her. Since the corner store was going to start selling clear files from his favorite anime that day, he had woken up early to go pick them up before they sold out. Mihari is overwhelmed with joy to see Mahiro going outside of his own accord. On his way back from buying the clear files, Mahiro stops by an arcade for the first time since middle school. He's enjoying a rhythm game when suddenly he senses a man standing watching him from behind. A few minutes go by when he feels a tap on the shoulder...

  9. ONIMAI: I'm Now Your Sister! S1 E4 still E4

    4. Mahiro's New Friend

    Mahiro loses to Mihari in a video game, so he has to do the grocery shopping this week as punishment. As an unemployed, good-for-nothing shut-in, the task at hand is daunting, but he plucks up the courage and makes his way towards the supermarket. The size of the crowd, however, makes his resolve waver and Mahiro finds himself cowering outside the store entrance. It is then that a young boy (?) around his age, wearing a baseball cap, comes to the rescue and offers him a helping hand. Thanks to the boy's (?) help, Mahiro is able to buy the groceries he needs and is just about to head home, when Kaede suddenly shows up. Seemingly, out of nowhere.

  10. ONIMAI: I'm Now Your Sister! S1 E3 still E3

    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...

  11. ONIMAI: I'm Now Your Sister! S1 E2 still E2

    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...

  12. ONIMAI: I'm Now Your Sister! S1 E1 still E1

    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.

Cast & crew

  • Yoshie Saito

    Yoshie Saito

    Erotic Game Voice (voice)

  • Hiroaki Miura

    Hiroaki Miura

    Seme (voice)

  • Hisayoshi Suganuma

    Hisayoshi Suganuma

    Uke (voice)

  • Emiri Suyama

    Emiri Suyama

    Clerk (voice)

  • Kumiko Nakane

    Kumiko Nakane

    Watch Stand (voice)

  • Reimi

    Reimi

    Child - Brother (voice)

  • Erisa Kuon

    Erisa Kuon

    Woman B (voice)

  • Yuuya Uchida

    Yuuya Uchida

    Leonardo (voice)

  • Hironari Nemoto

    Movie Narration (voice)

  • Kousuke Goto

    Kousuke Goto

    Spabone (voice)

  • Enako

    Enako

    Nicolala (voice)

  • Mitsuki Nakamura

    Mitsuki Nakamura

    Truant Officer (voice)

  • Yuri Ise

    Yuri Ise

    Student A (voice)

  • Ren Arata

    Student B (voice)

  • Rina Tsukishiro

    Rina Tsukishiro

    Nodoka Fushimi (voice)

  • Misaki Watada

    Misaki Watada

    Minori Shiina (voice)

ONIMAI: I'm Now Your Sister! FAQ

Will there be new episodes of ONIMAI: I'm Now Your Sister!?

ONIMAI: I'm Now Your Sister! has ended, so no new episodes are scheduled. The final episode aired on March 23, 2023.

When did the latest episode of ONIMAI: I'm Now Your Sister! come out?

The most recent episode of ONIMAI: I'm Now Your Sister!, Season 1 Episode 12 "Mahiro's Future as a Sister", aired on March 23, 2023.

How many seasons of ONIMAI: I'm Now Your Sister! are there?

ONIMAI: I'm Now Your Sister! has 1 season with 12 episodes in total.

When did ONIMAI: I'm Now Your Sister! first air?

ONIMAI: I'm Now Your Sister! first aired on AT-X on January 5, 2023.

How do I get notified when new episodes of ONIMAI: I'm Now Your Sister! are released?

Download the Streambay app, follow ONIMAI: I'm Now Your Sister!, and you'll get a push notification the moment each new episode is released.

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