The Unlimited Manga That Started with Attack on Titan

After a young man died, he accidentally obtained the adventure system and became a traveler. He traveled through various comic worlds and started his first legendary low-key journey in the world of Attack on Titan. In this world of intrigues and dangers, he understood that only low-key is the way to go. The same is true in Tokyo Ghoul, Sword Art Online, and Yu-Gi-Oh! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.