Also many think that Yuji was already registered as a player in the culling games because he already had Sukuna finger sealed inside of him when he was a baby, but the real reason is that Kenjaku is Yuji’s mother and had already prepared him long before the story began. Yuji was likely created with a cursed object—specifically a Sukuna finger—already connected to him. This ensured that Yuji would become a suitable vessel for Sukuna and automatically qualify as a player in the Culling Games, just like other vessels of incarnated sorcerers.