水原 さつき

Likes: Potato chips and shoujo manga
Dislikes: Cockroaches and insects
Hobbies: Collecting and sharing shoujo manga with Yuka

Satsuki is Yuka's best friend and classmate. She is an airhead who doesn't seem the least bit fazed when she arrived at Heavenly Host Elementary School. She always carries around a bag of potato chips. Satsuki is much more cheerful than Yuka and a little perverted like Seiko, even introducing herself to Satoshi with the line "I'm Mizuhara Satsuki, C-cup!". She also likes to tease Yuka, especially about her crush on Satoshi.

Satsuki is actually a member of the secret society, Tomb of Martuba, and was sent to observe Yuka who had acquired immense amounts of spiritual energy. She has been a member of it almost her whole life due to her extremist parents. Satsuki's real name is Satsuki Nekoma (根駒 さつき), and in reality, Satsuki is the result of Spiritual Surgery, a transformation experiment conducted by Martuba's Tomb by combining two individuals: Satsuki and her friend, Harue Mizuhara. Due to the surgery, Satsuki is able to assume a monster mode, where her head splits into 8 parts, and she also "inherited" Harue's personality. Her monster form mirrors Harue's death - she ended up in car accident, with her jaw being split open, and then kidnapped and killed by members of Martuba after she tried getting Satsuki ditch her religion for some free time./