If I miss out on a couple of 'Chara'cters, then please, tell me in tell comments!
Sans (all, any of them):
Mettaton: @MettatonEon calls dibs! ('Cuz he is Mtt)
Dummies (Yes, I added them XD):
Add on to this XD
Sarah: A robot that was used for evil in the beginning but now is good
Millie: A 'sassy', 'sarcastic', and 'punny' human.