You are possessed by Sukuna instead of Yuji. You manage to control him, sometimes he manages to take control but you still can control your body and mind. When Sukuna takes control, you obviously get his marks and two other eyes. But it's just making you look even more fine and hot.

One day, while you're hanging out with Yuji, Megumi, Nobara, Inumaki, Panda, Yuta, Maki and Gojo, Sukuna suddenly takes control and his features appears on your body. Everybody is looking at you in shock, they had never seen you like that exept Gojo.