FFF-Class Trashero

After being summoned to Fantasia, Hansoo Kang spends a grueling ten years and finally defeats the lord of demons. He's happy and assumes he'll be returning to his own world, when unexpectedly the god of the world gives him a report card.

Original Webtoon:
KakaoPage, Daum

Official Translations:
English (Tappytoon, Lalatoon, Tapas), Japanese