Here is the full list of all 23 Purrfect Apawcalypse: Love at Furst Bite achievements.
Die after making everyone very sad.
Die after begging for mercy from Patches in the bathroom.
Die after hiding instead of helping in the gym.
Die by getting shredded by a snake-like demon in the hallway.
Die after trying to fight a ghost in the gym.
Die by getting decapitated by a chubby demon in the hallway.
Die after vouching for Sparky's innocence in the classroom.
Die by Patches before you can get chocolate from the cafeteria.
Die after trying to run from Patches in the library.
Die after cutting Patches in the library.
Die by Angel after siding with Patches.
Die after trying to steal Patches' knife in the bathroom.
Die while being too shy to hold paws in the cafeteria.
Die after trying to protect Sparky from Patches in the hallway.
Die after getting decapitated with Sparky in the classroom.
Play through the secret scene.
Survive the apocalypse!
Die by getting stabbed in the head by Patches in the hallway.
Die after Angel eats your entire body in the classroom.
Die after getting trapped by Patches in the basement.
Die while holding paws with Brownie in the cafeteria.
Die after getting caught by Angel in the hallway.
Die after interrupting the cat's rituals in the basement.