I can't speak about bp's in particular, but it's fairly common for male animals to attempt or mimic mating with other males of the same species....but I've only heard of this when no females are available for them. Give them a female and they are no less inclined to mate with her than any other male. I'm sure the same is true of bp's. If you house two males together, they may lock up....but that doesn't mean they don't WANT a female!