Bruce is asking for the kind of patience that Tony has when he's waiting for FRIDAY to finish diagnostics on a suit, the kind where he can wait as long as he has something else to do in the meantime. He fully intends to keep Tony occupied in the lead-up, but that verbal commitment from Tony is absolutely necessary.

"I... might find out it's not really my thing." This is the hardest part of what they're trying together. The intimacy, the time together, nudity and making out, they've come pretty easily, but finding where sex works is complicated for more reasons than that the best case scenario for an accident with Bruce's body fluids is Tony getting very sick.

Trying to lighten the mood now that they've gotten that detail out of the way, he drops a hand to give Tony's ass a squeeze. "If it isn't my thing, we'll get creative."