Here's Monstrous Cavern, the first roegadyn I used to play as in Final Fantasy XIV. As mentioned in the wip post last month, he didn't get his own name til recently. While his appearance may be that of a Sea Wolf bearing a Hellsguard name it's because he's half of each, thanks to his parents.
Another (and yet rather fitting) reason for his name is because he's quite the bottom. Perhaps one day we'll see how truly deep his ass is.