You cycle through several of the "rooms" of the circus and eventually find the spot where they keep the dunk tank. You always wished to do one of these. Dunking, that is. You always saw it in cvs and tv shows that some nice asshole was sitting in a chair, and you could dunk them. You want to dunk anyone, it doesn't have to be an asshole, although an asshole would be more pleasurable.
Glossing over that ridiculous sentiment, it does seem a bit, unusual that this dunk tank was never mentioned before, yet is needed for the overall plot. There's a name for this, if only I could remember it...