Rosario + Vampire is a manga with the themes you mentioned. There is one human at a school for only monsters. Major conflicts between certain groups of monsters and monsters that are looked down upon (Witches kicked out of both human and monster world, Monstrels are hodgepodge monsters that are looked down upon). I'd recommend looking into the monsters from the series because the way that it describes each type of monster is done very well. But to put my opinion about what each of the monsters would be (mostly based on the way monsters work in Rosario + Vampire)
Twilight: Witch- Exiled monster that looks human but has very strong magical ability
Rarity: Succubus- Uses specialized magic to lure in people and make them fall in love with them, care about beauty over smarts
Rainbow Dash: Werewolf- Faster than a vampire (most powerful monster) but not as strong. In moonlight the abilities of a werewolf can't be stopped by a vampire.
Pinkie: Ghoul- Once human who now has the blood of a vampire infused with its blood. Needs a soul lock to keep the blood in check or goes completely insane and kills everything and everyone (can only be stopped by a vampire or werewolf). Can harness the power of the vampire blood through the soul lock when in danger or when friends are in danger.
Fluttershy: Doplegänger- Not very strong, able to hide by changing form into other monsters and copy their abilities, takes the strength of whoever they transform into, can also transform other people to look a certain way. (Nothing really has the ability over animals to my knowledge so I chose one that was a shy, weak one with an amazing ability of hiding)
Applejack: Vampire- Super strong, strongest of the monster world. Kind of OP but can still be beaten by a werewolf. Weakness to water of any kind unless treated with special herbs. Can use a Rosario to keep the vampire power in check. Does not look strong naturally but has an ability to call for supernatural levels of energy and power that cause super strength.