Herbert makes a helpless little noise in the back of his throat, because with that nibbling - well, it feels like a real kiss, and not Tony taking the piss, and that doesn't make any sense, and while he really still doesn't like Tony very much (especially since Thor is currently his ideal man), he's still a good-looking boy kissing Herbert which is pretty damn rare.

Finally, his brain catches up with the rest of what's going on, and he clamps his hands on Tony's shoulders and pulls back, gasping, dark eyes wide behind his glasses and cheeks bright, bright red.

"What are you doing?" he hisses. "We're in the library!"