Bruce needs to know that this experiment isn't going to break things between them; he and Tony aren't so very different in that respect. Creating Ultron had put a few cracks in their easy friendship that they're both choosing to overlook for the sake of filling in the empty spaces in their lives. Why not? Their lives are both so fractured that they've had to forget the idea of whole and just put the pieces together into a functional mosaic instead.

"Have you figured out the money problem?" Stepping back, he swipes a hand down his torso to wipe away the water droplets that cling to his chest and body hair. "Since we aren't thieves."

Tony isn't a thief. Bruce? Well, he doesn't have a pressing need to steal today.