Yes?? People have been visiting all night. [Of course his door's unlocked, imagine leaving it locked when expecting repeat guests. If he had to unlock it each time more kids came by, some would surely get bored and take the locked door as a refusal, and make good on their candy ultimatums before even issuing them to him. Papyrus is briefly indignant about this, as Sans should know about the trick-or-treaters, given he seems to be running from some...? Wait, that's strange.
The dim light of the jack-o-lanterns and street lamps isn't enough for Papyrus to recognize his brother's injuries for what they are, but between wanting to be sure he didn't lock the door, and wanting answers, he moves to open the door before Sans even reaches it.]
add on extra layers to build a turtle shell and hide from zombies
The dim light of the jack-o-lanterns and street lamps isn't enough for Papyrus to recognize his brother's injuries for what they are, but between wanting to be sure he didn't lock the door, and wanting answers, he moves to open the door before Sans even reaches it.]