What Should I Do If My Brother Is a Reborn Villain?

High school student Sayaka has a happy family, but unexpectedly awakens a substitute. Once, after mistakenly believing that a substitute messenger was attacking her brother, she and her brother traveled to a different world together. Immediately afterwards, she learned from her brother that her brother was actually the behind-the-scenes boss in the comics she had read who had not yet revealed his true face. Sayaka: Are you kidding me? ! * After the fourth battle, Madara was ready to return to the Pure Land. When he opened his eyes again, he saw a strange world in front of him. His body went back to his childhood and he became an "ordinary person". After getting his first taste of the world, he chose to be adopted by a childless couple. Later, he had a younger sister, and this younger sister started reading the popular comic "NA▇▇TO" after high school. Uchiha Madara:...... Good news, he hasn't appeared in the comics yet. Bad news, when he was twenty-one, his sister traveled back to the ninja world with him. * The second leader of Uchiha didn't just wait for his brother after he returned from a certain trip. His brother also brought back a sister of unknown origin. Izuna:? After confirming that the other party was not the illegitimate daughter left outside by his deceased father, Uchiha Izuna became highly vigilant - where did the enemy come from to confuse Madara! He will never admit that this guy with ulterior motives belongs to his sister! * At first, Quan Nai asked her brother warily: "Brother, she and you are just brother and sister?" Later, Izuna asked her brother cautiously: "Brother, are Sayaka and you really just brother and sister?" * 1. The male protagonist Izuna, Madara is a pure family line. 2. The main game is popular, the modern world view is JOJO, the timeline is in the early 2000s, the comics were serialized before the Fourth World War, the hand fetish box lunch in JO has been around for many years, the heroine and the strongest elementary school student are in the same period, and there are very few plots involving JO. 3. Apart from having a substitute, the heroine is a very ordinary JK. She may be biased, but she is still in the good camp. After time traveling, I was really worried that Madara would start a villain career again. 4. It should be an emotional flow... If it's off track, I'll delete it. 5. The reason why I gave Madara so many buffs and took so many detours to create a sworn brother setting is because I really can't think of how to make Madara give up the Eye of the Moon four wars ago. 6. The male and female protagonists are not related by blood and do not share the same household register. 7. Think of adding more. Intention: love and peace.