>>536375757
The Owl Girl isn't iirc, she's just the person working the front desk.
Meidri (the best girl from it) definitely isn't one either as she works at a inn/tavern hybrid, and she REALLY dislikes the idea, doesn't approve of it, and tends to be vocal about how she doesn't want them to be a bad influence on others. She farthest she normally goes is just smacking the human guy after he finds a new way to sexually harass her though. the catalyst behind her going into a primal rage and beating the everliving hell out of everyone was when she realizes that they all made four sex dolls in her likeness that looked and talked like her, then gave them different personalities based on what they were into and fucked them for their 'interview' that day.

>>536376164
>>536376393
I'd have to agree if we're talking all Monster Girls and not just like, 'typical' Monster Girls, then yeah Catgirls are easily the most overwhelmingly popular and I would also have to agree it isn't even close either.
There's a reason "Cosplay Tier" became a meme in the first place; it's (either jokingly or otherwise) pointing out what Monster Girls are slight enough to classify as "normal" for the average person, by way of being Monster Girls who look so barely different from a normal person in the first place that any human could easily look like one by just dressing up with minimal effort.
Succubi specifically also fit into a similar niche of being "normal" looking enough for most people while being spiritually more monstrous at least. Rather than 'demon girls' in general, I would say that it's Succubi (or Succubi-Looking Girls) specifically that would be second place.

After those two, when you start getting into the more "monsterous" Monster Girls, that's when I would say that Harpies are probably the most popular or recognizable of them, which is followed by Mermaids and Lamias in varying order as the three are undoubtedly the most iconic trinity of Monster Girls.