Leii's got that distinctive look—blue spiky hair, black eyes, and a lean build that fits his whole vibe. Fashion-wise, he's pretty recognizable: brown jacket over a dark tee, purple pants, long boots, black gloves, and he carries a sword. There's also the golden triangle necklace he wears, which has become kind of his signature accessory.
Personality-wise, he's generally the calm, rational type who thinks things through and stays open-minded, though he can lose his nerve occasionally. What's interesting is that his gruff attitude is basically a defense mechanism—he puts it on to cover up his self-consciousness, which shows he's got more layers than he lets on.
He grew up in Dentro's orphanage and is one of Ten's closest friends from way back. That shared history clearly shaped both of them.
Content compiled by AnimeList.moe from publicly available sources.