Far love (Frans)

Frisk is 10 years old and has fallen to the underground where she meets toriel and stays there for 13 years. When Frisk is 11 years old at the time that he meet a someone behind a door from toriel's basement. She starts falling in love with that someone throughout her life. Will goat mom let her out? If yes what will Frisk think when she meets him?

Sans' age is unknown and if he is older frisk doesn't mind someone old. Also frisk is a girl in this book.