Sans thought he'd lost one of the people he cared about most when Frisk gave her own life to stop Chara. As he sat there, rocking the child's still form, he made a promise... one that he'd do anything to keep. Then, a tiny skeleton baby with wispy, brown hair gives him the chance to make things right and Sans comes to learn the joys and pains of being a father to his little girl.

Yuni is the teenage leader of the Human mafia. One day, she falls down Mt.Ebott in hopes of freeing the Monster mafia. Along the way, she makes friends and gains the love of a certain smol skelly. (Sans x OC!Reader moments) Undertale belongs to Toby Fox. Mafiatale belongs to its creator. (UNDERGOING MAJOR EDITING)