Am I a Devil? Sorry, You Are Right!

Invincible + decisive in killing + absolutely no delay! Yang Lin practiced in another world for five thousand years, but returned to Earth and only five years passed. Then you can only become invincible, and slap anyone who is unhappy to death. Even if you are a genius, so what, all the ones I kill are geniuses! You have a background, haha, then I can only eradicate your background! ... Here, if I don't like it, I'll give you a slap in the face! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.