you were on a mission with Yuji, but, surprise-surprise..The principle tried killing Yuji again so a special grade was unleashed to attack you both. You quickly killed it with nothing but your hands.

Sukuna, (who resided in Yuji, since Yuji is his vessel) saw this and swapped out with Yuji. Sukuna looks at you

“hey. How’d you kill that thing so easily, fool?”