Home Is Where The Fire Is

Royal guard Papyrus and his lazy brother Sans hear of a human wandering the underground, who just happens to be the last soul needed to break the barrier. After surviving the ruins, the skeleton brothers come face to face with Ash Graves, a total loser that's somehow alive despite the numerous attempts on his life.

(Or: A wild human appears! Papyrus, catch them! and... Sans too, I guess...?)