I Learned to Kill Demons Through Demon Slayer: Kimetsu No Yaiba

A teenage boy travels to Demon Slayer: Kimetsu no Yaiba, what does he gain? A unique system and golden finger for each traveler! No, no, he didn't... Then how on earth could he survive in this crisis-ridden world? The difference between the background and the original work is that the Edo period in Japan is more than hundreds of years apart from Tanjiro's era. Su Yun had a question mark on his face? I have traveled through time! Hahaha! Etc! Ghost! Could it be that this world is Demon Slayer! Ah! I want to go back! I want to go home! I'm going home...