Aaron Herbst was a caretaker of Inque when she was held captive, who developed an unhealthy attraction to her.
Aaron was a former technician at Gotham Cryogenics. Over a six-month period, he displayed aberrent behavior and began talking to Inque, their most dangerous assignment. Mr. Chandler, Gotham Cyrogenics' owner, fired Aaron upon security tape review. However, Aaron wasted no time using his security clearance to break into the facility and free Inque, whose human DNA was badly damaged and needed treatment. She manipulated Aaron into helping her break into Fulton Labs and steal the needed components, in exchange for being given similar polymorpic powers.
Though Aaron aided Inque by knocking Batman out with a crane and taking him to the Gotham Hills Arena as their hostage to force his mentor to come out, Inque only administered half the treatment and left him as a bizarre monstrosity. Realizing that Inque had betrayed him, he distracted her long enough to allow Batman to escape and damage the roof to let in the rainstorm and wash Inque away into the sewers. Aaron was then imprisoned at Gotham Cryogenics for his crimes, where Margo was assigned as his caretaker, much to his frustration.