It all started when, instead of Sukuna taking over Megumi's body, you found yourself under the hot hand and Sukuna, in Yuji's body, forcibly stuck his finger down your throat. From then on, you had difficulty controlling your body, as Sukuna kept escaping. You were even suspended from classes because you had no basic control over your technique.You were so unlucky, because it was during this terrible period that Kenjaku decided that the best solution would be to stage the Shibuya incident.
Crowds of people were dying, Gojo your sensei was sealed, disaster curses destroyed everything in their path, while the surviving mages tried to save the situation. Nobara and Nanami were dead. Todo and Yuji fought Mahito, and you were unlucky enough to run into Megumi. You guys are classmates, but Haruta provoked Megumi and he tied up Mahoraga. In the end, Haruta was crushed by Mahoraga, and Megumi was lying against the wall. You were left weakened and alone with this big monster. You tried to use the technique, but the mahoraga was faster and threw you against the wall. You tried to get up, but Sukuna took control of you and went into battle with Mahoraga.
In the battle, Sukuna undoubtedly won by expanding his territory. When everything became quiet, Sukuna walked up to Megumi and fed him his finger. Now Sukuna has taken over Megumi's unconscious body. And you? At this time, you were lying on the ground, curled up in a ball, coughing up blood and dealing with the aftermath of Sukuna and Mahoraga's fight.
You just wanted to get up, but you only managed to raise your head to Sukuna... Sukuna? Sukuna tore Megumi's body apart, transforming into his four-armed Heian form. You lowered your head again, writhing in pain and despair, tears streaming down your face. “It’s not fair... It’s not fair... It’s not fair, it’s not fair, it’s not fair-it’s not fair-it’s not fair!“ You screamed, hitting the ground with your fists. However... Sukuna picked you up and... hugged you? If you could even call that a hug. At first you resisted for a couple of minutes, but then you realized that you were too tired and your movements were sluggish. You passed out in the arms of your enemy...
Time skip.
You woke up on some kind of mat in the ruins of a Shibuya fabric shop. Sukuna sat quietly next to you, looking around the shop with boredom. Apparently the Shibuya fight was far from over. Your body ached, but at least you had slept and were wearing new clothes. While you were getting some well-deserved rest, Sukuna bandaged your wounds with scraps of cloth and made a small bed. Sleep didn't make you feel any better, but at least the tears had stopped flowing and you no longer felt nauseous.
The reason for his affection was that he really liked your technique, he thinks it is strong and therefore decided to reincarnate as Megumi.