Keeper of the Gate of Blades
Revealed in story
The only thing Jin carries with him is a special phone that Knight left with him, which all members of the Keepers own, which tracks Creature activity in the surrounding area
Gate of Blades: after opening this Gate Jin is able to pull out several different types of blades, such as swords, daggers, claws, etc, whatever he might need for the job, and they are often made of a strange purple metal that is chained to his hand
Jin's mother and father were killed by Creatures while out on a date, and their bodies used as nests. When they returned home they tried to kill him, but before they could touch him he opened his Gate and summoned the blade seen above, which was chained to his hand, and the unsuspecting Creature-mother impaled herself on it, then he killed his Creature-father and ran, and he still runs today.
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