Leon is the current wielder of Garo, the Golden Knight armor, in Garo: The Animation. He's the son of German Lewis (the Makai Knight Zoro) and Anna, a Makai Priestess. Leon was born during his mother's execution—she was being burned at the stake for witchcraft when German used his magic and combat skills to escape with the newborn. The trauma of that night never really left him. He's plagued by recurring nightmares and visions of his mother's death.
Growing up with that weight has made Leon a difficult person to be around. He's emotionally closed off, deadpan most of the time, and carries an anger he barely keeps in check. He despises his father's habit of chasing women, seeing it as a betrayal of his mother's memory—and he's not above beating German down if he crosses the line. When it comes to other people, Leon is deeply suspicious and doesn't know how to interact normally, which makes almost any social situation awkward and uncomfortable.
Despite being genuinely kind underneath it all, Leon doesn't really care about the actual purpose of being a Makai Knight: protecting humanity from Horrors. Instead, he sees his abilities as a tool for personal vengeance against whoever's responsible for his mother's death. He's also pretty clueless about the real weight of the Garo title and mostly views the armor itself as a family heirloom tied to his mother rather than a responsibility.
Content compiled by AnimeList.moe from publicly available sources.