The hyena exudes a look of concern. It didnt even want to bite she forced it into this.

It isn't just an elongated clitoris, it's the folds and 'lips' of the vagina elongated into a tube. As for the reason? Well this setup makes penetration impossible unless the female is genuinely aroused, making it literally impossible for a male Hyena to rape a female Hyena.

Now making rape-pregnancies impossible is incredibly beneficial to the females of a species, so one might ask why more species don't have a setup like this? The answer is simple: the baby hyena has to come out of that tube, making labor even more taxing and dangerous for the female Hyena that the females of other species.