Sabitsuki (さびつき) is the main character of .flow, who is controlled by the player.
Sabitsuki is a female with white, shaggy hair. The default outfit she is portrayed wearing is a faint purple-gray sleeveless shirt, a white skirt, and red or purple shoes. Her mouth is only shown during select cutscenes and events. She seems to be a young teenager, as evidenced by her official drawings and appearance. Each effect alters Sabitsuki's appearance in some form.
- Sabitsuki's name continues the tradition of giving fangame characters a name ending in -tsuki. However, the kanji in Sabitsuki's name have a different meaning than the ones in Madotsuki's name. Sabitsuki means "covered in rust".
- According to the equipment screen, the skirt she wears is her favorite one.
- It is likely that the shape on the title screen of .flow is a very abstract depiction of Sabitsuki herself.
- It is theorized that Sabitsuki is slowly losing her mind either from the disease or from side effect of her treatments.
- The Kaibutsu also seem to have lost their mind as well (active chasing ones) or are on the verge of losing them (normal ones that will become active after hitting) which could further link that both Sabitsuki and the Kaibutsu are suffering the same disease/side effects from disease treatments.
- Sabitsuki possibly didn't fit in much at school and was either widely ignored or made fun of. Support for this theory comes from that going through the Corrupted School Kaibutsu will actively chase you with pipes as their laughter fills the halls.
- It is possible that Sabitsuki is being quarantined due to the disease she has.
- It is possible that Sabitsuki suffers from albinism, given how she has pale skin and white hair. It could be that this caused her to be bullied at a young age, due to her looking drastically different to the other students and teachers.