Thad's taken V-9 since he took his first breath. Taught how to create it himself and to use it in any scenario where his best wasn't good enough and he wasn't fast enough. His violent tendencies are multiplied, his temper is worse, and he isn't stable. Constant flashbacks triggered by everything around him, and hallucinations of his father. Actions he won't even remember. Causing damage to his body almost definitely his own life span.

He was addicted to it.

He could go mad with or without it. He's kept it a secret for a while until one day he can't find the injector or his dosage.  He searched for both  frantically only to find them  both destroyed on the ground. He turned to stare at you. Angry, confused his voice breaking and his speed kicking in at the same time..

"WHY? I NEEDED THAT! WHY WOULD YOU WASTE THEM BOTH?!" It was for his own good.

"This is what's making you sick. Velocity-9 is killing you!"