You may initially think that we've made a mistake when we listed the models in this scene, but if you keep watching past the introduction you will see that this scene is really with Adam and Chris Hoyt.
It starts off however with Adam and Billy explaining a bit about their relationship and history together, and inevitably leads on to some of their sexual conquests.... which is where Chris comes into the picture. Anyhow, probably the best explanation is for you to watch the clip and see how it goes.