He has a flirtatious attitude to match his charisma. Nonetheless, this palace playboy has a serious side to him.

Leo is a character who seems to wander off and do his own thing. He also has a tendency to tease and agitate others on purpose, which can be seen especially with Alyn. Leo tends to drop hints around the Princess Elect, insinuating that he knows more than he lets on. 

Behind his facetious exterior, Leo can be clever and cunning. His ability to discern situations and work them around his favour points towards his high level of intelligence. His experience with politics along with his astuteness makes him the second-best person to tutor the Princess Elect, behind Giles. 

Leo's personality is full of conflicts and contrasts that make him a rather complicated individual. He has two main sides to him: the one he shows everyone, which is for the most part acted, and the second, which he only allows the Princess Elect and Alyn to see. His personality in itself is best described as playful and teasing; he loves to tease and taunt people, particularly the Princess Elect, Alyn and Giles. He's extremely flirtatious, being extremely charismatic and socially adept, although in reality, he doesn't overly love the constant attention he gets from bureaucrats around the palace as a result of his charming personality.

(Bottom Line: Fucking flirt.)