I helped him move in.

You decide to play it safe. You say, "I helped him move in when he got here," and you leave out the details about how you thought you would have to have your lips surgically removed from Connor's penis, after four days of non-stop sucking.

Mark turns to you and says, "I hoped it was going to be you! Connor wrote and told me he was going to try to get the guy who helped him to pick me up. He said I could trust you."

Hmmm... So far, you haven't heard anything that suggests that Mark knows the extent of how much you helped his friend. Maybe you'd better keep that to yourself for now.

You nod, wondering what on earth he is going to ask (and hoping that it will be something along the lines of, "Would you mind terribly if the two of us get naked and stay together in a room all weekend, making each other cum repeatedly?")

Mark doesn't say anything. In fact, he looks downright uncomfortable, as if he hasn't completely decided whether he can trust you or not. You're going to have to coax conversation out of him.