Pinkie.
Everyone loves Pinkie.
Griffons, ponies, donkeys, everyone likes Pinkie. She's fun to be around, always so caring and attentive, and she's always so eager to please and enjoyable to be around. Anyone who knows Pinkie would only have good things to say about her.
Well, except for anyone she's put on her table. If the dead could speak, they'd only have terrible things to say.
Nobody knows Pinkie, not really. They know who she pretends to be: The blood splatter analyst who's extremely good at her job, and is friendly with just about anyone. It isn't their fault, she's been perfecting her mask for almost as long as she could remember.
No one really knows that she spends her nights stalking murderers, learning their schedules, finding proof of their crimes that she already knew they committed. Then she'd take them to her table, forcing them to confront their sins before ending their lives with surgical precision, hiding their bodies so they are never found.
All because she has this itch, this deep itch that only killing killers can scratch. The truth is, she feels nothing, besides her desire for death. But the facade is slipping, the more she kills the less she feels she has to fake.
Is killing monsters making her normal? Or is she a lot more sane than she thought?