That's the son. A nice guy as well, has almost no grudges against his parents, except little things, usually the reason is his father. They have a strangely normal relationship, as a parent and a child, the only thing is father treats him like a stranger. Quite literally, always jokes about not being his father, and tries to ignore the fact it's true.
 About Melon himself, he likes nature. He has better relationship with his mother who has a garden, and they can take care of plants and trees together, when Melon has a spare time. He usually helps his father with the shop, that includes as work with merchandise, so theft. He was taught to steal things for the shop, and got pretty good at it. Later in the future he will start trying to fight the habit of stealing everything.