He opens his mouth, realises he doesn't want to give the honest answer - which is that he doesn't want others to know he can't swim - and then quickly closes it again, looking briefly awkward before he smiles again.

"Well, most people were wearing it. I figured I might as well." And to quickly distract from his awkward moment, he moves up his arms to dramatically flex. At least he has some muscle on him - though it's not like he's some huge ripped guy, obviously - so it doesn't look totally ridiculous. "And I look pretty good, right?"