Alright, brace yourself.
Heckyl is... sad, to say the least. His father was killed while serving in the military, and his mother died of an unknown disease a week after Heckyl's 18th birthday. He decided to sign up to the Amestrian military, hiding his depression behind his humor. When wounded by enemy soldiers, he was patched up by a medic who later became his girlfriend. In fact, she's the reason he started learning alchemy in the first place. Then... both Heckyl and his girlfriend (now fiance) were involved in the Ishvalan War of Extermination... she was kidnapped by Ishvalan rebels and killed. Heckyl lost most of his emotions that day. He became apathetic and emotionless, picking up smoking and heavy drinking, to the point where he can drink 20 bottles of whiskey dry and remain fully sober. To add insult to injury there, his arm was severed by one of the Ishvalans who captured his girlfriend, and he had to build his automail prosthetic himself. It was painful, since each individual nerve had to be connected to the arm one by one with a pair of tweezers. To this day, he has yet to show any real emotions, other than anger, frustration, and tiredness.
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