>>21105902Given that Barbaracle has legs, I doubt that it keeps the need for a disproportionately huge penis. It's a costly feature to maintain outside breeding, so much so that in several duck species, the penis is detached at the end of mating season because it energetically cost efficient to just regrow such a long one later than it is to pay for the upkeep on something effectively useless most of the year.
Also, I doubt each head on the Binacle/Barbaracle has its own penis. I think we're to take it as that they are one organism, and again, it's super costly to have and maintain such a disproportionate penis.
With all of this in mind, my answer goes to Binacle.
