Yuusha? Iie, Tada no "Ippanjin "Bakemono" desu (Previous title) (Associated Names)

In the summer when I was 16 years old, I was summoned to another world as a hero. After that, a psychic, an alchemist, a sage, spirit mage, Demon Lord —being summoned by many other worlds, I repeated a lot of meetings and partings. Lives I could save; lives I couldn’t save. Hatred, sadness, happiness;…