If he's honest Ianto is actually impressed Jack's organized all this, even with his obvious ulterior motives. It's true though, they don't do things like this much and it might be nice to change that, to make this actually feel like a relationship all of them are involved in, instead of a relationship he has individually with two people who occasionally sleep together. Whatever the case this should, hopefully, be a nice evening. It's pool in a bar so he's dressed down today in jeans rather than a suit but with the way Jack keeps glancing at his ass and smirking - he is not as subtle as he thinks he is - he gets the suspicion he won't be wearing them all night. Predictable.
He pushes open the door the the Blood Shack, glancing around for Spike and smiling. "Do you ever get any real customers in here?"