Friend goes where your mouse does. Bring them to the tree to eat, bring them to the egg to... Who knows what that does, and bring them to Gaster to *snd_splat.ogg* Click to make Friend laugh.
This started out as me trying to figure out how to code movement for Friend's tail. I think I know how to do it properly now, but this was fun to play with. Oh also thanks a lot to the Spriters' Resource, they're really helpful when it comes to getting sprites for Deltarune :3