Sumireko Usami is a character in the series Touhou Project. The main antagonist of Urban Legend in Limbo and is the main protagonist of Violet Detector. She's a human from the Outside World with psychic powers (ESP). She is the first president of the Secret Sealing Club. She is a strong psychic, an individual capable of various powers associated with the paranormal, including but seemingly not limited to levitation, pyrokinesis, hydrokinesis, telekinesis, psychokinesis and teleportation.
- Sumireko finds Shinmyoumaru Sukuna adorable, claiming to want to take her home as a pet, much to her annoyance.
- Several Doujinshi books concerning her relationship with Fujiwara no Mokou were released and sold by many fans.