Nekomata

Once King Frost is defeated, the area will finally warm back up to normal temperatures, and frozen doors will be unlocked.

King Frost will later reappear in future games referencing this interaction like he does in SMT V, where he turns a warehouse into cold storage and fights the Nahobino over a fish that he wants to give to a Nekomata.

[laughs] What? Okay.

You gotta keep playing that game too.