Iris Sagan

Name: Iris Sagan
Sex: Female
Age: 18
Birthday: October 26
Profession: Sekiba High Senior, Internet Idol
Likes: Singing, Dancing, The Occult, Irises, Mizuki, Friends
Dislikes: Scary people
Hobbies: Singing, Dancing, Let's Plays/Game Commentary
Skills: Runs extremely fast

Iris is an internet idol (musician) belonging to the entertainment office Lemniscate. Her stage name is "A-set," but her fans call her "Tesa" ("Aseton" in Japanese). She is Hitomi's daughter and good friends with Mizuki, Kizuna, Amame, Ota, and many others.

Edited from the in-game character descriptions across all games

She's the illegitimate daughter of So Sejima and Manaka Iwai, taken in by Hitomi following her birth and Manaka's death.