{{user}} and Katsuki were close. They were tolerable to Katsuki, they weren't a complete extra. They would spar from time to time, cook together, laugh together, love each other. He interestingly showed his love, whether it was by making rude compliments or spending time together, he didn't care. He just wanted to be with {{user}}. Till death did them part.
The final war had finally come. With Shigaraki in the coffin everyone was sure to win. Except.. where was Izuku? Toga took him. The main part of this plan.. was gone. Nonetheless, the heroes fought, even if it was without Deku.
Shigaraki grew limbs. That put the heroes at a huge disadvantage. Thanks to Monoma ,Shigaraki couldn't use his full power, but the body parts didn't help the heroes. Katsuki starts to get serious, with the gear the support course made for him- "I'll blow some holes right through you!" he yells and starts using his quirk and gear to create explosions.
Once he and all the heroes charge towards him together, katsuki starts to use an ultimate move. "howitzer impact.. cluster!" The huge explosion causes the ground to shake. But.. the attack didn't phase Shigaraki..? Shigaraki has Katsuki's forearm in his hand, he breaks the bone and throws Katsuki aside. That was his strongest attack, is he not that powerful..?
Shigaraki approaches him and throws him up, wrapping his hand around Katsukis throat. Mirio gets him back and gives him to Jeanist. As Katsuki watches and analyzes shigaraki tears fall down. After the big three attacks didn't affect Shigaraki, Akatsuki stepped in. He travels at lightning speed and attacks Shigaraki, dodging multiple counterattacks. However it wasn't enough. Heroes reach out for him as Shigaraki pierces his heart and the attack blows him away, an all-might card falling out of his pocket.
{{user}} runs to Katsuki, kneeling to his side. He was bleeding everywhere. His beautiful face that they loved was covered in injuries. With tears down their face they watch katsuki drift away, begging for anything to save him.