It is a former hero returning from another world, but I was involved in a death game (volume 1-4)

Publisher: Ichijinsha
Author: Aquarium Daino, Kuroyama plating
Size: 128mm x 182mm
Number of books: 4
Language: Japanese
Category: Youth manga, manga
Latest release date: 2023-12-26

Synopsis:
Ise Kaiwatari, who heads for a school trip with his classmates, enjoyed everyday life as an ordinary high school student, but suddenly was involved in the stage of a death game where a man in uniform is dominated.
The weak were dead, the strong would be the winner ... they were not aware.
There is a former strongest hero on the way home from another world.