Sans has been depressed, that's why he acts so chill, he knows that one day the pacifist routes are gonna end and you're gonna try something new, Dillon you're wrong, hes always had it

Sans only becomes depressed when you kill his bother

NOT TRUE SANS HAS FRICKING DEPRESSION THATS WHY HE TELLS PUNS CAUSE HE IS AFRAID FOR PAPYRUS TO BE KILLED sorry but I looked on the website and a Video that is a backstory of chara and she says sans has depression I'm sorry this is what happens if I know UNDERTALE to much