Faun

Faun is someone who worries a lot. While he wears a frown when he's busy, he's quick to put on a smile when someone approaches him. Given that person is someone he likes. Despite helping others, there are a few people who see him as mysterious. Some find it interesting and some find it dangerous. He doesn't remember much of anything before he arrived in Monstadt. He claims he only knows of collecting a debt and after that, finding out the mystery behind his lost past.

He doesn't know his own limit sometimes and will often put himself into an exhaustion period. He tries his best to hide it, but Diluc and Zhongli are the first ones to notice it. He'll keep going and looking for clues about his past and whatever debt he's supposed to be collecting until he drops. While he's aware of the risks for doing such things, he continues to do them. His love for adventure and seeking out his forgotten past has become his life. He's quick to flash a smile and say he's okay, only reaching out to the two most important people in his life when he just can't take the pressure anymore.

His fighting style is light, fast attacks. He's quick on his feet and bounces slightly on his toes when he comes to a stop in battle. He uses his Pyro abilities to distract the target, then using them to slash into them with multiple fast strikes. He gathers all of his Pyro energy into the blade of his sword before a battle. He does the same with his hands when he's in a pinch though that usually results in him burning himself. When he gets really excited in battle, he plants his sword into the ground, channeling his Pyro energy to burst from the blade, causing a blast of fire to burst out in pulses, effectively damaging any enemy that gets too close for a few seconds.

He seems to have many friends that adore him. He doesn't have many enemies unless you count the bases of Hilichurls and Raiders.

Fun fact:
The marks on his face is a tattoo that he doesn't remember getting so he's sure it's from his past.

As for Voice claim:
Keith from Voltron fits him best!
https://www.youtube.com/watch?v=eGtJtGeap1A