Sekai de Ichiban Warui Majo

Quinta is a notorious witch with a reputation for cruelty and killing other witches, despite being only 16 years old. She is mysterious and has lived for more than 300 years. She unexpectedly takes on the role of bodyguard for Nestor Gilroy, a professor with five PhDs who is being targeted due to his unpublished research. Accompanied by Quinta's animal companion, Feeyo, the trio sets out on a journey to ensure Nestor's research is published.