Han is joking with Chewie about taking advantage of a sleeping Leia. Luke is very upset by this, thinking they're making real plans. To wind up Luke, Han tells him that he'll take Luke instead. Luke agrees, and Han is so turned on by how furious and reluctant Luke is that he taunts Luke about going next door and taking advantage of Leia instead.
Han/Luke, dubcon, Luke sacrifices his virginity for the Princess