Meanwhile, Lily and Marshall recall how, minutes after agreeing to wait and make their first time special, they had sex in their college dorm room while Ted sat uncomfortably in the top bunk. Barney attempts to pass off "Dirty Dancing" as the story of his first sexual encounter, which confuses the gang. When Robin recalls how she lost her virginity to a guy who admitted he was gay barely after initial penetration, Lily says it did not count as sex, which the rest of the gang disagrees with. Marshall then suspects that Lily did not lose her virginity to him, which upsets him as he believes that Lily losing her virginity to her ex-boyfriend rewrites their shared history as a couple.