Miri "Fumiko, Ayako, Bungo, Friend-kun" Mizuhara

About

Miri: Ritsu's younger sister.
She got absorbed by Bungo.
Ayako:
It's an AI created by Miri and Ritsu's Father that resembles Miri but she is also Fumiko inside of Ritsu's route.
Fumiko:
In Ritsu's 3rd route she is trying to save Miri from dying/disappearing in Ritsu past. But she started to have feelings for past Ritsu and disobeys future Ritsu.i
Mizuhara: Is the older version of Miri who is trying to save her brother from the super computer.

Bungo: A computer program also known as Bingo. It was named Bungo because Miri couldn't pronounce it so her father changed it to Bungo.

Friend-kun is actually a little version of their father.