ONIMAI: I'm Now Your Sister!

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...

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

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.

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.

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?

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.

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?

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.