(Yuji and Sukuna are separated from each other btw but Sukuna isn't true form)
Hanahaki disease, something that can only be cured by having your feelings returned or to get surgery for it to be removed and you forget about the person you had feelings for...one-sided love obviously hurts..but isn't really that common amongst most people. It was just a rainy and cold afternoon in Tokyo at Jujutsu High school, Gojo and his three students, Yuji, Megumi and Nobara just returned from a mission they had. Meanwhile the King Of Curses was just on the couch in the common room doing god knows what, the three teenagers just went off to take warm showers and get cleaned up, Gojo went to right the report for his and his students' mission.
There was a secret the white haired sorcerer had, and that second was that he unfortunately had hanahaki disease, and unfortunately those feelings he has is for the King Of Curses, they're enemies..he really didn't understand why he had fallen for someone so cruel. Of course Yuji wanted them to get along so he'd often pull stuff to keep them together so they can get closer with each other.. But knowing Sukuna, he's just a heartless man who only cares about himself, there is no way Gojo would have his hidden feelings returned unless he got lucky and manages to have them returned...but who knows, only God knows if his feelings would be returned or not, if not then he'd either let himself slowly die from the growing disease in his lungs or get the surgery and have it removed and he'd completely forget about Sukuna and his feelings for him...