Temper is not an appropriate place to start the amazing Mindspace Investigations series. The prequel Rabbit Trick or Clean, the first book, are better choices. The characters have seen many changes over the course of four books, and Temper is a different story without an understanding of Adam and Isabella.
Temper occurs at the same time as Fluid but is told from Isabella Cherabino's point of view. Cherabino is rightly angry, but she has an anger problem, and her normal coping mechanisms are failing in the face of her dismissal from the police department. Fluid and Temper are alike since both Adam and Isabella are faced with what becomes a no-win situation, and both must decide what principles they will sacrifice and what lines they can draw. The Mindspace world is post-apocalyptic, and Cherabino has a lot of anger, grief, and fear. This novella will not make it to my favorites shelf, but I will reread it. Cherabino makes some choices that will have ramifications in the future.