He is an introvert human who has a hard time adjusting to being a tinpig due to his new body 

They go by they/them so there's no confirmation for if they're a male or female by the author 

so, either male or female will do 

Though he likes to shout at how he feels since lumen is the only person, he trusts due to a misunderstanding he's afraid of Pokémon though he has no problem speaking his mind