user
Given a cartoon image and a caption. Caption: It seems you promised them herd immunity, sir. Question: Generating an explanation of why this image/caption combination is funny. Answer: 
assistant
A play on words: "Herd immunity" refers to a group immunity to a virus, but here -- the herd refers to a herd of sheep, and the immunity isn't viral: it's legal immunity, as evidenced by the two wolves dressed as lawyers. The sheep are mad because they are in unexpected legal trouble.