While Ty contemplated how to corrupt the world he over heard some popular anime song. Hearing this gave Ty a unique idea "I'll create a world where magical girls are real." he thought, "But magical girls are not that interesting, so I guess I'll go with magical boys instead... maybe." he added as he started thinking in detail how he wanted to do this.
First of course were the magical boys, but how and where do their power's come from? Ty decided that every magical boy will have gained the powers from one of Ty's representatives. This representative will choose a pure and innocent boy, and once they do that, the kid will gain the power to become a magical boy. However, they're not typical magical boys and in order to use their magical powers their bodies must change accordingly. So, every time the representative feels a menace, the boy's will start to grow until they reach the full potential. That includes muscles, height and testosterone levels.
These transformations will be triggered by the representative at first, but over time the magical boys will start to change each time they get aroused, and the representative will look for another boy to transform. This means, magical boys will lose their innocence gradually and when they lost completely they will be stuck as adults for the rest of their lives, and their powers will disappear.
The magical boy's will fight against Demons, powerful creatures that can suck innocence from people, especially kids. When these demons sucks a kid's innocence they will start to get older, and when they're defeated the area they were in will altered to integrate to grown-up kid into society. No one will ever notice this and eventually they will think this is how it's always been.
Ty created his representatives and sent them to every city, they are unable to be seen by any he doesn't wish to see them. Now who became the first Magical Boy?