Ren is a social, sweet, and trusting tiefling who also goes by "Pyro," "Firefly," or "Py". Ren probably isn't his actual name either, but it's what he goes by. He's a wonderful cook; being able to control the temperature of the fire under his pan certainly has played a large part in his ability to do so. Ren thoroughly enjoys experimenting with new recipes, even if they don't turn out the best. He's very passive, and will listen to just about everyone no matter what they ask him to do. If a known enemy asked him to play tic tac toe in the midst of a fight, he probably would; unless one of his known friends had explicitly told him to do something else. While he usually remains friendly and kind to others, he has no problems harming others if asked- and he can and has done so without question. Similarly, he will share most information freely if asked, but likely will not diverge anything (including important things) otherwise.

The only thing he's really firm about are the removal of his goggles. Ren rarely takes them off, to the point where he sleeps in them. He only takes them off when he absolutely needs to, and only when he's absolutely sure he's alone. The glove on his dominant hand is a deterrent to keep him from accidentally playing with fire around others. He often plays with fire unintentionally, so the glove is his way of remembering not to. While he can still bend through the cloth, he finds it annoying. The rune on the poncho's button is the moon glyph for "blood." It symbolizes a deal he's made with a Hemomancer named Zephyr. 

Zephyr is the only person at the moment that Ren will reliably listen to, seeing as he trusts him deeply. Ren and Zephyr have a deal where Ren willingly lets Zephyr draw blood from him daily for use in his blood bending. Because of this, Ren's neck is almost always sensitive because that's where Zephyr likes to take it from. In return, Zephyr has sworn to protect Ren with his life- though truth be told, Ren made the deal so he could have a friend on his journeys.  

Ren's past is something he doesn't like to talk about. He had originally come from a happy home with his biological parents. They weren't very endowed in the terms of gold, but the family was enough for the young tiefling. One day, a rich elven couple happened to find him training with his siblings in a clearing close to his home. The couple met and talked with Ren's parents, and a week later, Ren found himself leaving his home; adopted by the Elven couple. 

While he didn't know it at the time, his biologically family had sold him off to the elves to be able to support their other children better. His training was enhanced, and he learned to use his fire bending in a fight. He was also trained in the art of the scimitar; essentially making him a weapon. The elves, eager to make back the money they had spent on the child, illegally enlisted him in an underground fighting arena. They hid how young Ren was with dark clothes and a half-mask, covering his mouth. His eyes were left visible, simply because black tiefling eyes were uncommon, and thus a good selling point for the 'persona' they made for him. Afterwards, 'Charcoal' quickly rose in the ranks of the arena. The fighters started to know him better as 'Black eyes,' and the rumors spread all the way to the top. He was undefeated thus far, unbested by all but one. 'The King' had been the raining champion for decades, and did not take kindly to the new rising star. Their match lasted what seemed like ages, seeming equal for a long while before 'The King' started to tilt the match in his favor. With the last swing of 'The King's' blade, his opponent fell to the floor, having nearly been cleaved in half. It was now that the crowd could see the tiny face, no longer obstructed by the mask that had been split down the middle. 

Ren woke up in an unfamiliar house, miraculously still alive. 'The King' stood over him, menacingly. He had healed the boy out of respect for his excellent skills in the arena. The fact that a child had nearly taken down the longstanding champion of the ring still did not sit well with him however, and as soon as Ren could stand, he had handed him his things and told him to get out and never return. Ren did, leaving his town and wandering from town to town- doing small tasks and jobs to get by. Years later, he was sitting in the woods, wandering just as he had all those years ago when his encounter with a blood bender changed his life forever...
*Fun fact: Ren's name actually is derived from "Renaissance," or rebirth.