I Traveled Through and Became the System of the Son of the Plane?

Have I traveled through time? There are no adults, no reincarnated animals, no possessed weapons or anything like that... To be precise, it's not even a living thing. I! A great young man in the new era of the 21st century! Time travel and become someone else's system, the kind of coexistence and death! He is still a son of a plane, the kind that provokes the ceiling of combat power at the beginning! "Hey, is this the underworld? I'll make an appointment to get a number, and I'll be reincarnating soon..." This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.