Close as children. Even close as adults. Prince Asriel finds a young girl in the Ruins. He takes her back to his small home. Humans find out about one of their kind living with the monsters. They take the girl back to the surface, leaving the young prince heartbroken. The years pass and the girl gets older, as does the prince. She goes back down into the Ruins and reunites with the prince. They fall in love not long after that. This is their love story. Their future is bright, now that they are reunited... (Contains some sexual content and may contain some harsh language)

Undertale romance fanfic AsrielxFrisk(female) After Nilu (Frisk) manages to save Asriel at the end of the Pacifist route, they make a promise. That no matter how long it will take for Asriel to reincarnate she will wait. Seven years pass and Nilu finally reunites with Asriel. After his reincarnation Asriel and Nilu become best friends. And Nilu starts developing feelings for a certain Dreemurr.

Years and years of remembering his name. The name that had changed her life in the space of only a couple minutes. She kept her promise, and visited him again. But when she found him and brought him back, an old SOUL makes her return. I changed the title. Title name courtesy of newnewhome