So the other werewolf girl manga this one's obviously trying to go after is Tsumiki (Ogami).
This one is Tsukimi, at least according to page 16 - I haven't seen the raws, but one reading of that is 'beautiful moon'.
I think having tsu and ki in there for 'moon' is probably the theme. And then 'mi' for beautiful.
And then yes, Pyon is the sfx rabbits make when they're jumping.
Small correction, her name doesn't use the kanji for beautiful but rather "see" (月見 is the name).
"Kawaru" also means "change" so the whole name implies the typical relationship between werewolves and looking at the moon before turning.
And I think people already made the some connections but to start from the top mochizuki's name is 望月which means "full moon", thus creating the relationship that he is the full moon that makes Kawaru turn. And as others said, "pyon" is the sound effect for rabbits jumping, and there's an old Japanese tale about rabbits living on the moon pounding mochi, so it all kinda ties up thematically with Mochizuki being the rabbit and Kawaru being the wolf that wants to eat it.