Isekai Shoukan wa Nidome Desu
Translation not done by me Credit to Kuro Translation
As the world of 〈Eclair〉is in danger as the war between the Human, Beastman and Demon race waged war, a man was summoned to save the world, and he indeed save the world according to his mission, and returns to the Human Country. However, what was waiting for him was the trap of the Human King, who was afraid that the Hero who acquired power would take his position. Trapped, the Hero was put under transfer magic, being born again as a baby in modern times.
16 years later, He spend his high school life by the name Suzaki Setsu. He continued looking for a method to return to the different world again, even if he receive bullying as a gloomy guy who always read books, he continued looking for it non-stop.
But suddenly he once again step on the soil of the different world. Summoned by the hero summon of the Human country........this time along with his classmates.
"War again? Sounds troublesome, don't wanna."
Fortunately, he was summoned to the different world of 5 years later, slipping out of the Human country, he decided to meet people such as the good old Demon King and the Beast King.
However he keeps on getting caught up in nasty plot, this is the story of the former hero who doesn't have the motivation.