one round clown
A boyfriend who can only have sex once and then passes out shortly afterward. It could mean that he is too old, too drunk or he doesn't find you that attractive to have sex with you again.
Girl 1: Aww girl, me and my man did it ALL-NIGHT last night! He wouldn't stop. He went for five rounds!
Girl 2: You are so lucky! My man and I only did it once last night. He is a one round clown.
Girl 2: You are so lucky! My man and I only did it once last night. He is a one round clown.