That's the sort of thing Bruce thought was a good joke and got a smile out of him? No wonder Tony was having such a hard time cracking him. "Oh, maybe that's why she's into you all of a sudden," Tony realized, shrugging his blanket up around his shoulders so he could have full mobility to grind up against Bruce, "she likes it doggy style." This was the perfectly echoing kind of hallway for an enthusiastic howl into the dark, which was cut abruptly short, along with Tony's gyrating, when the ambient colour from his spell that had floated away pointedly shifted. She found something. Taking Bruce by the shoulders again, this time to spin him around and leap onto his back, Tony commanded, "After 'er, boy!"