user
Given a cartoon image and a caption. Caption: I think my wife is having us tailed. Question: Generating an explanation of why this image/caption combination is funny. Answer: 
assistant
The man is cheating on his wife with this other woman, and apparently she has noticed. Sometimes, to prove their partner is cheating someone will hire a private investigator to spy on the cheating spouse --- however, this private investigator is not being subtle, he is literally in the middle of the bed while the cheaters are in the act of cheating. It's funny because the man has somehow not noticed the obvious investigator until this point, and still seems unsure of his existence.