Eternal Mangekyo Sharingan From the Start: Saving the Campus Belle

(Spirit Realm dungeons + campus belle + wish fulfillment + Sharingan) [Ding! You have obtained the Eternal Mangekyo Sharingan.] Zhang Feng asks, "Bro System, whose Sharingan is this? Which Uchiha big shot does it belong to?" [You can use anyone's, but you'll need to expend mental energy to transform it!] Well, then, isn't this basically an all-purpose Mangekyo? Spirit Realm dungeons are scattered throughout the world. To clear them, humanity awakened supernatural powers and entered the Spirit Realms to conquer their dungeons! Zhang Feng had planned to lie low in an S-rank Spirit Realm. After all, this Mangekyo consumed mental energy, and a man's mental energy was his very vitality. He couldn't afford to waste it. But the campus belle was there too, and a troll had captured her! With her life hanging by a thread, Zhang Feng decided to show a little gentlemanly courtesy. Amaterasu! "What kind of technique is that?" asked the team members around him, terrified out of their minds. "Uh, spirit fire? Right! I released my supernatural power, spirit fire!" Zhang Feng hurriedly made up an explanation. After all, people in this world had never heard of Naruto! With a ridiculously overpowered skill like this, it wouldn't be wrong to call myself a god, would it? In a world of Spirit Realms, those who conquer them reign supreme!