Probably just "regular" mammals.

Mammals have a lot of weird dick things. Some bats have gone from penetrative sex back to just like touching genitals because their dicks are so huge they literally don't fit anymore.

https://www.livescience.com/animals/bats/bats-with-weirdly-giant-penis-have-sex-for-up-to-12-hours-in-a-way-never-seen-in-mammals-before

So having a impractically huge dick was more important for some reason.

Guess something similar happened with hyenas vis-a-vis having become matriarchal at some point.