Review Detail of MiddleEastern in Returning from the Immortal World

Review of the first 15 chapters ~~~~~~~~~~~~~~~~~~~~ If someone were to live for 10 thousand years, then his actions would be very different from a normal human. Our MC supposedly lived that long and yet acts like kid, it's mentioned times how arrogant he was in his previous life and how strong willed he was and yet again act like a kid. Somewhere in the story he get kicked out of his class and he gets shocked, i don't see why a 10 thousand year old Being, who fully knew how bad he was performing and how his teachers hated him gets shocked by such decisions. His background is just for show and never really reflects on him. The story doesn't adds up, its like the author had bunch of ideas but didn't know how to stick them together so he just decided to mention all of them without making a relation.