In Petscop 2, Paul walks behind a bookshelf at the back of the Quitter's Room and unintentionally causes Quitter to desync, seemingly now moving by her own accord. When Paul first passes behind the bookshelf and causes Quitter becomes desynced, the same sound effect plays that was originally heard when the door to the underground in the Newmaker Plane opened.
Quitter may have connections to Tiara because of the note in the Quitter’s Room.
Because Quitter seems to have the same body as the player character and generally appears to be a composite of multiple images, it's possible that the AI invented her to depict a character that wasn't in the original game using existing assets.
An image that seems to be modeled after Quitter's face appears in Petscop 1, hidden in the load screen when Paul crosses from Even Care to the Newmaker Plane. Her face appears to be vertically squashed and partially obscured in this image.It is possible that the entity obscuring Quitter's face could be vomit, or even excrement, as a transcript addressing Candice Newmaker's eventual death states:
"Twenty minutes into the [rebirthing] session, Candace had vomited and excreted inside of the sheet; she was nonetheless kept restrained."
Despite this, it is also possible that the obscuring mass could be anything from a pair of hands to a simple graphics abnormality.
Both Quitter's and the Quitter's Room's names could very easily be linked to Candace Newmaker's death.
This is primarily shown when, forty minutes into the infamous rebirthing therapy session, Candace's adoptive mother, Jeane Newmaker, asked her "Baby, do you want to be born?" while she was struggling in the sheet, to which Candace weakly replied "no". In response to this, one of the two psychiatrists present, Julie Ponder, began to jeer at Candace's lack of action with the morbidly playful phrase "Quitter, quitter, quitter, quitter! Quit, quit, quit, quit, she's a quitter".