Maybe this is an unpopular hot take, but I think a good monster girl design should struggle with day-to-day life in a human world. If your monster girl can live a normal human life where her greatest inconvenience is wet dog smell or people assuming her tail is fake, you need to mix more monster in your girl.
Harpies who can't write or type or open most containers with their wings. Werewolves who worry about hurting someone if they get overstimulated at the wrong time. Minotaurs with digestive systems and metabolisms which require grazing throughout the day, not the three big meals humans are used to.
Lamias who have to stay home in the evenings and during cold months to stay warm, otherwise their muscles stop working right and they get stranded. And they're sick of their human friends suggesting they get some kind of tail sweater. It wouldn't help, the problem is that their body doesn't produce enough heat to begin with, and anyways a tail garment would get in the way of their rectilinear locomotion, and there's no way a sweater would survive being walked on in the first place. It feels like they don't actually care about you being stuck at home whenever they go out, they just want to feel like it's not their fault they never see you.
If your monster girl can't be read as some kind of disability allegory, you're doing something wrong.
