Su-jin could be petty, too. Su-jin could say that he chose Aqua because he's Vena's antithesis in every way imaginable. But he's not here to put Aqua in an awkward position or piss Vena off needlessly. He will, however, pointedly brush Vena's hand away from himself.

"And you've always been good at not including everyone present in a conversation."

Glancing at Aqua now trying to hide, he holds his hand firmly so he can't shrink too far away. "He's protecting you from his abilities."