Codename R/Al, she is the twin sister who joined together with Masami.
Identity and daily life
A second-year student at Kyoka Academy High School, right-handed, still makes mistakes after joining the team, and admires Ishtaru.
Character relationships
She is the twin of Masami; She is the only team member in this group of profiles who can make edible dishes.
I/O・B′: the final handshake
At the end of the B′ route, Mayumi and Aoi Hinata shake hands and smile at each other.
Related entries
- Appearances:I/O
- Twin sister:Masami Shinozuka (I/O)
- Team:Criminal（I/O）
- B′ Ending with Mayumi shaking hands and smiling:Hinata Aoi (I/O)
References
- REGISTA: I/O Character Introduction (Original Official Website Archive)
- LEIBSTANDARTE MITUKI HAYASE：ボクハココニイルヨ
- GAME Watch: I/O original character preview
Data compiled on: 2026-10-10.