You've Already Cultivated Immortality, so Why Should You Practice the Sunflower Manual?

Ning Xiaochun traveled to another world and stayed in Novice for a hundred years. After coming out of seclusion, I thought I was just a martial arts scumbag, but I didn't expect that this was just a martial arts world. And then... He becomes invincible. "Little brother, I see that your bones are amazing. You are a unique genius. This secret book is given to you." "Go away, sir. I've already become an immortal, so why should I practice the Sunflower Book?" This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.