expression
despite appearances; even though they look that way
Fixed expression used to contrast someone's outward appearance or impression with their actual character or ability. Often followed by a surprising or positive trait.
ああ見えても、彼はとても優しい人だ。
Despite how he looks, he's a very kind person.
ああ見えても、彼女は実は料理が上手なんだよ。
She may not look it, but she's actually a good cook.