Height: 172 cm
Weight: 51 kg
Chest: 85 cm
Blood Type: O
Birthday: June 30
Zodiac Sign: Cancer
Specialty: Super High-school Level Swordswoman

Pekoyama comes off as a very serious and stern woman who shows little to no emotions. She speaks with an authorative tone of voice, and she is mostly business. However, she is not antisocial or unwilling to stay around the other students, even agreeing to attend Togami's party in Chapter 1.

In her first Free-Time Event, she reveals that she has a strong affinity for animals, though they themselves do not share the same feeling.

Near the end of Chapter 2, it is revealed that she is the personal bodyguard and hitman of Fuyuhiko Kuzuryuu, having been taken in and raised like so by the Kuzuryuu family. She sees herself as not a human being, but rather as a tool, with her only purpose in living being to protect and follow the orders of Kuzuryuu.
Peko is the killer in Chapter 2.