Sabitsuki (さびつき)

Overview
Sabitsuki (さびつき) is the protagonist of the game .flow. Little to nothing is known for certain about her. When prompted to leave her room she shakes her head, in a similar fashion to Madotsuki, leading many to believe she is a hikikomori or quarantined. The dreams she experiences tend to be dark and violent, suggesting her personality or past experiences are of the same nature.

Appearance
Like Madotsuki, her eyes appear to be always closed in-game (with the exception of her Eye and possibly Cat effects), though fanart and artwork from lolrust depict her eyes as being black or red. She has short white hair in a lopsided bed-head style. Most fans like to speculate that Sabitsuki could have/suffer from albinism.

It's interesting to note that many of the hospital children and all of the Kaibutsu have white hair as well, which evidences possible speculation of the color being the physical manifestation of a disease.

Sabitsuki wears a dark blue-ish purple/indigo top with a turtleneck collar and no sleeves. Additionally, she has a white skirt and red shoes. Each effect slightly alters Sabitsuki's appearance, without changing her basic design or shape.

Her equipment screen (called "Myself" in-game) has her whole equipment listed as:


 * Hair: Bed hair
 * Clothes: The usual
 * Skirt: My favorite one
 * Footwear: Leather shoes

Personality
In the fashion of Yume Nikki-styled games, the protagonist does not speak and much of her personal history is left to speculation. Many in the Western fan community depict her as one of the more volatile or grim of the Dreamers, while in Japan, Sabitsuki tends to have a more approachable personality, despite the violent nature of her dreams.

Throughout the game, there are motifs involving illness, hospitalization and social exclusion, many suggesting that Sabitsuki is or was at some point in her life affected by a deadly disease of some sort, possibly one that may have separated her from her peers at school. It can therefore be theorized that she is an excluded, introspective individual.

Whether this is just a consequence of her status as a "disabled" person (having this disease) she has learned to deal with or Sabitsuki longs to reach out to other people is unknown -- though it should be noted that the vast majority of the humanoid figures she sees in her dreams have parts of them decaying or (badly) injured.

Sabitsuki seems to dwell on the unfortunate events of her past or negative thoughts that enter her mind: most of the dreamscape is comprised of dark and depressing elements, with the few exceptions of the Famicom world and the Rave Area. From the latter of these dimensions, wherein is found the Headphones effect, it can be speculated that she is or was an avid fan of electronic music and technology itself, this interest being one of the few things she sees in a positive light.

Rust (錆)
By obtaining all of the effects in the game and depositing them in her PC, Sabitsuki transforms into a new version of herself, Rust. Rust cannot use any of the effects in the game, but can access three areas, that were previvously inaccessible, in order to obtain three empty boxes and obtain the last, and often considered true, ending. As of version 0.15, she can also reach an alternate version of the corrupted school.

Rust's physical appearance is the same as Sabitsuki's, except the color palette, which is more pale. In light of this and events of the third ending, many believe that Rust is Sabitsuki's more violent and diseased counterpart.

Having no access to the effects leaves Rust defenseless, though it should be noted that in lieu of the Kaibutsu there are now Red Demons in her dream world. These, upon contact, do not send the player to an inescapable area, rather, do physical damage to Rust. With each hit by the Red Demons, she becomes more decayed, until the point where she collapses and wakes up. It is theorized that the Red Demons represent a part of her disease.

Past
There are many theories about Sabitsuki's past, the most common being about the "Rust" illness and Sabitsuki possibly being in quarantine, or has locked her self inside to avoid catching the virus. Many NPCs in her dreams have been thought to be connected to Sabitsuki before her sickness worsened.

Other Game Appearances and References
Sabitsuki is frequently referenced in the fangame reference rooms, due to being the protagonist of one of the most well-known Yume Nikki fangames.

Trivia

 * Sabitsuki has been said to look like Gintoki Sakata from the manga Gintama.