Jealousy

Description: After papyrus finds out sans has magic, powerful magic, he gets mad at sans wondering why he didn't tell him, he said it was a secret, papyrus then told sans to teach him his ways, but in this version, papyrus refuses to believe it was and thought everyone knew except him, he would go on a rampage and killed the human he killed a few monsters in the underground he didn't kill Mettaton, Alphys, Asgore, Toriel, Asriel, Undyne, or anyone else like that, he got to the 6 human souls and used the 7th human soul as well and he became this melted monstrous being and he was going to finish the job, sans was able to get papyrus back to normal and explained everything to papyrus, now it's just like the normal old days of the underground, but sans will forever be haunted by what he has seen, what his brother has done.