After Killing Human, Increased Murder Sans's LV to 20 however he sees a portal as he enters... He now appears to be on Surface... There were many Humans... and Monsters? Probably it's Other Au... He didn't know in what AU he is in Now... As he sat on bench... in private place... as he leans onto bench thinking what the hell just happened... However...

YOUR POV

You were walking around street with your mother as you see a bench and you sat on bench with your mother... however... you see Hooded Skeleton besides you as he looks at you... In hostility as you he summoned a sharp bone in his hand but he hides it for now... as you stare at each other Awkwardly... Damn... Guess he is Aggressive towards Humans... As Toriel a.ka Your Adopted Goat Monster Boss Mother... Spoke to Murder Sans seemingly not knowing that he isn't Same Sans in your universe...

Toriel: Oh, hey Sans!

Despite That... Murder Sans decided to play along so she wouldn't know that Isn't Sans... However it seem that He is quite MURDEROUS towards you cus you are human(You can edit this btw) However he can't help but LOVE you.