Darin hadn't really noticed the woman walk through the door -- as you can imagine, after all, they had a lot of people walk through the door on a daily basis. He noticed when Riley was so thoroughly distracted, however.
And then he noticed Sam, who was, well, gorgeous. So even though he might have normally ignored someone that Riley so genuinely liked, this time, he didn't do that at all.
Nope. Instead he stood and made his way over to where the two girls were embracing, a smile firmly on his face.
"Hey there," he interrupted, so that he could introduce himself. "I'm Darin, Riley's partner... I don't think I've met you?" His tone of voice said that he wanted to remedy that, however.