Seigi's a college student with serious ambitions—he wants to work in public service someday. His name literally means "justice" in Japanese, and he genuinely lives up to it; he's got a stronger sense of right and wrong than most people you'd meet. He's friendly and honest, though he'll admit he sometimes lets his emotions run away with him.
The guy ended up working part-time at Jewelry Etranger after asking Richard to appraise a jewel. He's decent at household chores in general, but he's actually pretty proud of his pudding-making skills.
Content compiled by AnimeList.moe from publicly available sources.