misty is going to kill people. she's going to be, surprisingly, quite good at it. she'll use her position at the hospital to smuggle drugs out to poison people with. she'll avoid a physical confrontation as much as possible because she is very small and would get absolutely knocked over.
her reasoning for doing this will also be a bit less... guilt? although you could call it that. she doesn't judge other people for lying, but she'll grow increasingly paranoid about her own lies, both in canon and in ashbrook, and will have a light bulb moment of "what if i just kill everyone who could expose mine and lottie's secret!"
i don't thiiiink i'll do the superpower prompt but i will have a prompt available for the forest walks. she will be a very enthusiastic and very annoying partner but there will be an edge of paranoia and self destructive longing to her too, like she's a bit overly cautious about being stuck in the woods and is probably thinking about who they'd have to eat