Gabriel De Lightly is the eldest of his three siblings and as of right now, he currently resides at the Cult's HQ located in Russia. As a high ranking member of the Cult, Gabriel usually spends his time in meetings and with his co-leaders Katherine De Lightly and Kieran De Lightly, who also so happen to be his siblings - if that wasn't obvious from their last names. Although he has no interest in a relationship he is currently single and despite his actual age being 75, Gabriel has the appearance of a male in his mid twenties.
After being held captive and undergoing intense torture by the hands of Yamori; Gabriel's personality changed drastically, originally being kind and gentle. He trashed his previous ideology of "being hurt rather than hurting others," pledging to crush those who dared threaten his place of belonging. He adopted the habit of cracking his fingers from his torturer, Yamori. In his subconscious, Gabriel Strangled "Gabe," the image of his old self. This displayed that his new personality over powered the old one and took a tight grip of Gabriel. Gabriel became ruthless and brutal in order to protect his family, yet he managed to maintain complete composure. He no longer fears this new personality and was more violent during battles.
Gabriel is still capable of showing his gentle nature in front of people he cared about, but instantly turns merciless against his enemies. He yearned for strength and power, therefore becoming more arrogant. His new creed — that as "the strong" he had the right to "devour the weak" — was originally an ideology held by Yamori. Although it hasn't been asked, a lot of people assume that Gabriel developed some form of mental instability during his torture.
The oldest of the three, he was what caused what happened to them from the very beginning. Always an ambitious one, he was heavily involved in the politics of his time and as a teenager, he had gotten involved in some rebel groups against the Soviet Union. When he was sixteen, his abilities became to show and he struggled to hide it. Even harming his siblings due to his powers. When he was twenty years old, he was arrested by the Soviet's for protesting.
Tortured for information, he caused one of the biggest disasters in Moscow, nearly killing three hundred officials due to his loss of control. With his outburst, he and his siblings were taken by the Elementals. Being as not accepting of tri- elemental's as they were back then.
A kingdom, finding an opportunity of the three siblings, hid them away in a science lab. There, the three were tested on repeatedly. For four years, they remained in the labs but were soon deemed failures and the three were scattered as servants to different dukes.
But whatever they were tested on, soon it became apparent Gabriel was not aging. Disappearing into the night, he tracked down his siblings and they pledged to bring down the royals. Bring down the royals to bring an age of equality and prosperity.