Mephisto's Black Rose (Unlimited Trainee Fanfic)

"Infinite Trainee" fan, about the continuation of the black-haired Zongjiu and Mephistopheles in the extra story. I really wanted to write it after I finished reading it in my sophomore year of high school, and I kept putting it off until my freshman year. Welcome to taste::?(?σ??σ?)?:: Intention: Live a happy life and make progress every day