Francene Orsini, later known as Frisk, after she abandoned her past, was something of a hero to the monster race, befriending them and changing their hearts away from the violence their hope hung upon. She remained in the Underground following her neutral run, growing up with the people who truly cared for her and helping them find a non-violent way to escape, and when she was twenty-one, wedded Sans the skeleton. Three years afterwards, the events leading to the glitch occurred, and she was ejected from the Underground with the power of the deceased Toriel's soul by her husband.
After her ejection from the Underground, sent on a mission to retrieve more human souls and to ensure her safety, she was brutally beaten and raped in an alley while searching for aid, and admitted to a mental facility when she insisted that she needed to return to helping the monsters living under the cursed mountain. She was chemically restrained while in the asylum’s custody, her magical pregnancy undetected by common human instruments, and both she and the baby were adversely affected by the drugs.
Once released into her mother’s care at risk of the facility being sued for malpractice and abuse, Frisk spent the rest of her days in delirium, calling out for Sans and wasting away until the day of Aliza’s birth, where she died with her child in her arms.
Her body was laid to rest, but her spirit lived on in Aliza, a guiding light and good spirit leading her towards the truth. She guides Aliza in the form of a red butterfly. Watching over her daughter.