In the scene where Greg and Pam are talking after everyone is ate breakfast, Greg says to Pam "...I don't feel comfortable wearing your dad's boxers." Pam tells Greg to go borrow clothes from Denny, thinking he is still asleep. As Greg goes to Dennys room to get clothes, you see him going through a drawer and pulls out a pair of red boxers. Denny walks in through the window and startles Greg, so he puts the boxers back in the drawer. After talking some, Denny takes clothes out of his closet and hands them to Greg. There are no boxers that he pulled out of his closet, and Greg didn't take them out back out of the drawer.