And, much like working out in the gym, you'll barely break a sweat by the time I'm exhausted.
[Because, yes, Tony's beginning to get a solid feeling for Steve's sexual stamina, and it's just as ridiculous as the rest of him. Tony has no chance of keeping up, even though he's half Steve's age. Biology isn't his field, but he's starting to feel like he might need to try dabbling in it (and what could possibly go wrong there?)]
no subject
[Because, yes, Tony's beginning to get a solid feeling for Steve's sexual stamina, and it's just as ridiculous as the rest of him. Tony has no chance of keeping up, even though he's half Steve's age. Biology isn't his field, but he's starting to feel like he might need to try dabbling in it (and what could possibly go wrong there?)]
Totally unfair.