Leo is a character appearing in Pokémon Adventures. He is Hugh's roommate, and a fellow student in the Aspertia Trainer School. He placed 8th in the Unova Pokémon League, and is the Type Match-Up Expert of the class.
Leo is an easily flustered kid who believes in his friends and Pokémon, caring for them deeply. He believes that there are no bad Pokémon, only bad trainers who can make Pokémon do bad things. He gets flustered when seeing anyone cute, to the point of being practically unable to talk. He enjoys being around his friends.
Leo is a short kid, with short black hair that he wears under a backwards green hat. He wears a green t-shirt, and an orange Pokémon suit similar to that of a PokéManiac.
Black & White
Leo is first shown in the line up for the Unova Pokémon League. His first battle is against Cheren, who he loses against, earning him 8th place in the League. Despite losing, he doesn't seem too upset, and actually praises Cheren for his battle. However, as Cheren is under Team Plasma's influence, he brushes Leo off, making Black angry. Even so, Leo roots for Cheren in his battles, as he says he wants the one who beat him to be the one winning the tournament.
Later, he's shown fighting alongside the other trainers against Team Plasma.
Black & White 2
In this arc, Leo's first seen coming out of the bushes after Blake breaks up with Yancy, asking if she's gonna be okay. Blake assures him it's alright, and compliments the girls in their class as they head towards the school. Leo asks how Blake is able to be so smooth, and Blake tells him to have more confidence, and that he should be really popular after doing so well in the Pokémon League. Leo disagrees, saying that the events with Reshiram and Black were huge, so his achievement didn't compare.
The two sneak into the classroom together, but are stopped by Hugh, who calls them out on arriving late and says they should take the class more seriously. Cheren, who is now their teacher, tells them to settle down, and sends them out into the hallway, where they first meet Whitley.
Afterwards, the class battles to see who the strongest boy and girl in the class are so they may receive Pokédexes. Leo loses to Hugh, who loses against Blake, making Blake the male dexholder of the class.
The next time Leo is seen is when the class takes a field trip to Pokéstar Studios to learn about battles. Leo remarks how he's excited about the upcoming field trip, as well as the choir competition that's after, and Hugh retorts that he shouldn't be so happy. Leo also notes that Whitley's been fitting in a lot more with the class after she befriended Yuki, Yuko and Maya.
On the bus, he tries to get Blake's attention to sit next to him, but as Blake has plans to get close to Whitley and find out her connections to Team Plasma, he sits beside her instead. When they arrive at the Studios, Leo and Hugh both watch the show put on by Whitley and Blake, impressed by the performance.
Upon arriving back at the school, Hugh gets angry at the girls in their class when they bring up his sister, and Leo has to hold Hugh back from hurting them. The two find the pendant that belongs to Whitley, containing information on Plasma's records and a picture of N.
Leo and Hugh return to their dorm, where Leo asks Hugh if he doesn't get along with his sister, as he got so mad when she was brought up. He brushes it off, and asks where Blake is, to which Leo responds that Lack spends most evenings by himself. Hugh states that it must be nice having a room to himself, making Leo worry that he's a bad roommate and a bother. When Hugh goes to read what's on the chip stored in Whitley's pendant, he gets angry, causing Leo to worry about his friend.
In the next book, Leo is seen assisting the class in gathering chairs and other things for the choir competition that is occurring soon. He's told that they haven't arrived yet, and to Leo's relief Blake offers to help check on them and get them there for the competition.
As the choir competition is beginning, Bianca introduces Leo to Hugh's sister, and asks him to take her around and get her to her brother. Leo, though flustered, agrees and helps her find her way. During the competition itself, Leo manages to sing rather well through his excitement and stress, and Class E's Team Jigglypuff manages to win the competition with the help of Blake's Dewmaru.
As a prize for winning, Class E is allowed a trip to Castelia City. Leo falls asleep on the boat ride there, waking up just in time to rush off the boat. As he and his Deino are running out, however, they run into Hugh's sister, who had snuck onto the boat. Upon seeing Deino- a Pokémon she feared due to traumatic experiences with them- she panicked, falling backwards off the ship, almost into the ocean until Leo catches her. He gets embarrassed, as he's holding someone's hand, but he manages to pull her back onto the safety of the boat.
Leo apologizes for Deino scaring her, and she says its alright, explaining why she finds Deino so frightening. Leo says that he doesn't think there are necessarily and bad Pokémon, only bad trainers who make the Pokémon do bad things. He lets Hugh's sister pet the Deino, to try to help her overcome her fear of the Pokémon. Hugh comes out and sees them, and asks Leo to keep his sister's being here a secret, a promise Leo says he'll keep.
Later on, the main BW2 crew finds a man who's been hurt badly by Team Plasma. Hugh decides to go after them, telling Leo to protect his sister. He says he believes in him, as he was a strong trainer who managed to make it to the Pokémon League, and he trusts him.
Later in a flashback, Leo is shown being one of the three people challenged by Benga on his first day, alongside Blake and Hugh.