He feels her tense up a little, for just a second, but then she seems okay again.

"He's not kidding about liking to cook," he tells her as they follow Sherlock. "He's probably excited to have someone new to cook for, he already knows everything about what me and Tony eat."

He lets the inclusion of himself in her remark slide by, because isn't this what a good boyfriend would do? How could he do anything else?