[It's hard to tell with skeletons, but it does seem like Gaster's smiles more, just a little, at Frisk's attempt to offer their hand. The usual method is a little tricky now, isn't it? Ha.]
Yes, it is.
[An odd comment when someone is giving you their name, but the implication is clear:
no subject
Yes, it is.
[An odd comment when someone is giving you their name, but the implication is clear:
He knew that already.]