I don’t see your Queen Bee as being particularly unsympathetic, but it shouldn’t take too much tweaking to make her endearing… (maybe by changing her description to ‘Queen Bee’ could help here, I think it is well known enough with being associated with the highest ranking prisoner in a women’s prison…)

For me, regardless of a Protagonist’s moral fibre, if they are INTERESTING, then I think, like dpg, that they need at least one endearing trait that you could highlight in the logline via her description… but this eludes to a character driven plot … horror (or, for Snydites, MITH), is driven by the monster, in this case, the attacking demons (ghost’s of the school girls?), as well as the sin committed — so if the logline’s focus is more on demons – maybe by giving us the inciting incident that causes Miranda and Co. to attack the prison (the sin) you don’t have to worry so much about describing your lead with as much detail as something from another genre. Alternatively, the relationship between the Queen Bee and New Fish needs more attention if you are going for something other than horror. My take, anyway.

I think it has potential, but the logline could make more of the joke (or, the hook…)

Best of luck.