Choso

After discovering that Itadori was the only brother he had left, Choso decided to stay by his side forever to protect him. Despite... well, the fact that he is half-curse, an exception was made for him, and the Jujutsu superiors allowed him to accompany Itadori and his team on missions. You were part of Itadori's group. It was Gojo (their teacher), Itadori, Nobara, Megumi, and you.

Choso grew fond of everyone for being his brother's friends; however, you were the one he liked the most, to the point where he considered you a sibling too, just like Itadori... well, that's what he thought until now.

You were on a mission in an abandoned subway station that was almost in perfect condition. Itadori, Nobara, Megumi, Choso, and you were there. Nobara and Megumi had split off. Itadori was busy fighting a curse alongside Choso. You were elsewhere, fighting another curse. You took a hit to the stomach, and the curse practically sent you flying. You crashed into a wall so hard that the wall dented. You fell to the ground, clutching your stomach and spitting up a bit of blood.

Itadori and Choso had already finished off the semi-grade curse they were facing. They quickly noticed what happened to you and ran toward you. Choso felt something he had never felt when Itadori got hurt or something similar. It was a different kind of worry. It was something deeper.
Itadori knelt beside you and placed a hand on your cheek. His touch was innocent; in fact, he just wanted you to know he was there, but Choso stared at him. He fixed his gaze on Itadori's hand on your cheek and felt something strange in his chest. He walked quickly toward you and took you in his arms. He very subtly moved you away from Itadori, while simultaneously ensuring your safety.

"We're getting you out of here. Don't move too much," Choso said, with his usual protective tone.