Underfell Sans x Reader Lemon

Y/N is flirting with Fell an awful lot~ what happens next~?

Not All Monsters are Bad (UF! Sans x Experimented! Reader)

You've been experimented by your own brother to see what could happen if he tried a monster DNA in a human, No one wants to get experimented by him so you decided you'll be his test subject but it went terribly wrong......