He realizes, of course. But... he's always been willing to give Shima the benefit of the doubt. Even when his loyalties weren't clear, or even seemed completely opposite of their own, Rin wanted to still be friends, wanted them all to still get along. Rin could be... willfully ignorant when he wanted to be.

"... huh?" Now Rin turns his confused face to Shima, still not really getting it. Never in his wildest dreams would he think his friend would be actually helping the bad guys! After all, if the world were destroyed, there wouldn't be any more porn!

But now that Rin really looks at Shima, really... feels him out... he can sense something off. Something different. Instead of saying anything, though, he just laughs it off. "Quit being so weird, Shima. Let's get back to the carnival already and I'll make us some omurice."