[By the time Juno surfaces, Ren is right there ready to smile down at him with a look of complete innocence (that's kind of ruined by how obvious it is that he's trying not to laugh).]

Well, you were rude to me first, so I'm allowed to get payback. And it's my birthday, so being rude to me today is even worse, right?

[He says that second thing in a rather exaggeratedly dramatic tone, as if it's some Awful Transgression that must be highlighted. Still, once he's done saying that, he shifts back into a smile again as he plucks at Juno's shirt sleeve.]

You're going to be pretty soggy if you leave that on now, though.