So we're all good with a scaly dragon woman but not a Gater Girl? What's the difference? Extreme sexual dimorphism could be in full play, like with the Bat Breeders.
If we look at the Bat Creatures as a species they are a species of humanoid bats. The males are more bat-like (animalistic) in appearance with arms that end in wings. While the female Breeders lack wings (instead they have fingers & apposable thumbs) & have a distinctly feminine, human-like body. Heck even their face is closer to a sharp features woman (if u ignore the big ears, bald head & shart teeth). And if u try to get a BJ from you're Breeder at lowest she will bite MC's dick off so she isnt exactly the safest creature until fully domesticated that is. The whole reason we keep her? She lays eggs that we can harvest for magic & potions.
Now let's look at the Gater Beasts. If we imagine the ones we have seen are all male specimens then we can work with that & have the females be more humanoid/feminine in build (with perhaps a less pronounced/lizard like face- mabey closer to an Argonian from TES) & have them appear in mabey a Nesting Grounds in the swamps. They could have an Alpha Male who allows them to make babies but anything else causes eggs to birth (no young- like most birds & reptiles who havent been fertilised). Dunno what potions the Gater Eggs could be used for (mabey Invisibility or Sleep Potions?) But I like the idea of a reptilian pet for the dungeon & it could work IMO if we follow closer to the Bat Breeders. Instead of using the Stun Spell mabey MC will have to use Syringe to catch one & then speak with Erevi about keeping her in the dungeon.
You might say "but shes a predator that will bite MC" so is BatBreeder AND Venomina but we got them on side eventually. Mabey MC will have to buy a Muzzle from Harold before he can safely let her out the cage.