And monstergirls, including salamanders, aren't out of place?
Saiyans are a very specific species written by Akira Toriyama. Super strong humanoids with monkey tails that transform under the full moon.
You can have a human with a monkey tail but it's a silly idea to take the name of Saiyan.
If you're going to add Saiyans you may as well add Lucario. Or Vulcans. Or any other copyrighted races.
Monster girls are based off of public domain mythological creatures, y'know, like some of the CoC races such as Nagas and Centaurs.
But having a female character with a snake tail doesn't automatically make her associated with some anime.
Calling characters like Helia "Monster Girls" is almost demeaning since you're essentially accusing the writers of CoC of ripping off other
pieces of modern fiction.
CoC is supposed to be it's own thing. Not a fucking fanfic.