An (evil) pixie? There's close enough in power and appearance that you could use her given statistics for her, reskin and/or maybe switch out minor abilities (give her DR/cold iron instead of silver, fer instance), and change her sting to a poisoned needle or some such. If the players ask why she's different from other pixies, you might say she was altered by the Arcane Nazis using what ever blasphemous, crimes-against-nature sort of augmentation program that these sorts always have. Instead of trying to get back to hell, she might be trying to get back to the First World/Fey Wild/wherever fey come from in your game world.
If your Arcane Nazis have some sort of occultic ideology, perhaps they summoned Blosodriele from there? (Or perhaps she came as a result of a failed summoning of something else?)