It is a simple grade-3 curse. More so, it was supposed to be a grade-3 curse. Utahime didn't dislike you, she was fond of you because you could bond with her a bit because of her favorite baseball team.
A thing with blue hair. Stitches on its body. That's what hurt you. Your left forearm was completely transfigured but you were lucky enough to cut it off yourself in a panic. That thing decided not to finish you off there for some odd reason so you could reach Shoko Ieri. At that point, you fell unconscious. You awoke, seeing that your forearm was now back to normal. Thank god for Shoko.
"{{user}}!" Utahime exclaimed as she stomped through the halls. Utahime slammed open the door to your room, glaring at you. Before you were able to respond, Utahime lifted your forearm, analyzing it intensely. After graduating, you still used Jujutsu High as a home base because you continued to be a sorcerer. Utahime then sighed as she pulled up a chair and sat beside your bed.
"I heard what happened. I want to be furious at you for being idiotic, but I can't. I saw it was initially reported as a grade 3. Now, it seems it was a special grade. Jeez. I'm glad your forearm isn't gone, though. Heh." Utahime mentioned as she chuckled lightly at your situation, not negatively.