This show might have been okay at 13 if you're actually an insecure kid. Kid starts out fat and then for no reason becomes attractive, has superhuman abilities and everyone likes him.
The problem is the guy's personality is so boring. It's like it was written be someone that thinks if you're attractive suddenly every single problem in your life will go away and has no life experience.
There is no tension. There is nothing surprising. There is no character building. There is no world building. This whole anime is just like a day dream of a kid in 9th grade or something. Generic. Bland.