Let me recommend an anime doujin novel with a reborn teenager as the main character," The Diamond Ace, Sawamura Eichun." The main character was originally a weak young man with heart disease, but he was reborn into the anime world and got a healthy body from the main character of Diamond Ace. He worked hard to change the outcome. Through his own hard work and strength, he became the main shooter of the Diamond Ace. This was a heartwarming and touching novel, and there would be exciting competition scenes. I hope you will like this novel.😘