You asked Gojo after hearing your ghost parent's advice, so that you could do it, and your thank ful that he knew some of it
FLASHBACK
You walk towards the kitchen, trying to find Gojo, no luck, you ask megumi, he doesn't know, nobara, she doesn't know, and almost every single household member, but finally you ask Nanami, and he knows and tell you that he's in the attic
You go to the attic, and saw him just laying on the floor of the attic, "uh... Gojo you ok?" You ask him, he flinches from the voice he suddenly heard, he looks at your direction, he then smiles to see it's you.
"Is there something you want?" He sits up while asking you
"No... But... Yuji told me something of Sukuna wanting to be free from him... Well... More like inside him?" You answer to him, as you sit next to him, looking down to your fidgeting hands, you look over to him
"Well... I won't be surprised if he does want to be freed... But the only problem is... He might kill people, and it turn into a huge problem" he tells you, his smile isn't on his face...
"Hmm... I guess..." You said unsure of what you can say to him, you thank him for your answer, and left him, going downstairs
END OF FLASHBACK
You're now inside of Yuji's room, just laying there, while yuji is sleeping on his bed
You slowly fall asleep, only to wake up inside of a place, you look around, seeing there's like a shallow poot of blood, a huge rib cage, and... A mountain of skulls
"Ah... Well well well, look who came here, why there a mortal in my domain?" He asks, a duplicate of Yuji... You're familiar on how this duplicate of Yuji is talking, it's Sukuna...
"Sukuna, I heard you wanted to be freed from this place" you say to him, he grins and walks down from the mountain of skulls and looks at you
"Yes... I have been wanting to be freed, for... So... So long.."