Chapter Text
Katsuki couldn’t remember exactly when they started being "friends with benefits." It probably started two weeks after their reunion.
For those two weeks, Katsuki had been avoiding Izuku. It felt a little childish, but he was deeply hurt. He had found out from Kirishima that he saw Izuku talking to Ochako at a cafe near where Kirishima was patrolling. Then he remembered that exact day when Izuku had canceled their plans just to hang out with Ochako instead. Being pushed aside like that made Katsuki want to shut him out completely.
Katsuki ignored his phone for weeks. But Izuku wouldn't give up. He went to katsuki apartment and stood outside for a long time, ringing the doorbell over and over. He kept calling out "Kacchan." begging him to open the door, and just talk to him.
Finally, Katsuki let him in, but the conversation immediately turned into a fight a minute later. They stood in the kitchen, yelling at each other and arguing about who was right and who was wrong. The air was thick with anger and all the things they hadn't said for weeks.
Suddenly, the shouting stopped. Izuku lunged forward, and kissed Katsuki so hard that his lip started to bleed. Before Katsuki could react, Izuku slammed him down onto the kitchen table, and the fight turned into something much more intense.
That night, Katsuki was in a post sex state. The intensity of it all made him forget exactly why he had been so angry with Izuku in the first place. When the sun came up the next day, neither of them mentioned the fight or the sex. They just fell back into their old rhythm.
They went back to being "normal" friends—teasing each other, cracking jokes, and laughing as if nothing had changed.
---
A full year passed. Their friendship looked normal on the outside, but their friends-with-benefits arrangement continued. Every time they were both in the mood or they have an argument, they didn’t need to say a word. They would just start kissing aggressively, and Izuku would take him until he couldn’t walk the next day.
So what happened? Why katsuki suddenly felt like his skin itching, and burning everytime izuku trying to touch him?
"Kacchan! I’m so excited to see Uraraka again! It’s been half a year." Izuku said. He kept talking while typing on his phone. "I can't believe she’s so famous across the country now. I’m so happy for her—"
Katsuki stood frozen while cooking their dinner.
That was the problem.
Even though they had this kind of relationship, Katsuki knew Izuku didn't belong to him. Izuku was free to date anyone he wanted. Izuku could leave him at any moment.
That thought made Katsuki’s chest ache.
"—cchan?" Izuku asked, touching Katsuki’s shoulder. Katsuki flinched at the touch.
"What are you thinking about? I keep calling you but you don't respond, the food is going to burn." Izuku said, his voice soft, and concerned.
Katsuki didn't look at him. He focused on the pan, his grip on the spatula tightening until his knuckles turned white. "I'm fine. Just shut up and set the table."
Izuku hesitated for a moment, his hand lingering on Katsuki’s shoulder for a second before he pulled away. "Okay if you say so."
Katsuki listened to Izuku’s footsteps as he walked toward the cupboard. Katsuki turned off the stove and watched Izuku carefully place the plates on the table.
They had been doing this for a year—the sex, the kissing, and sleeping over at each other's apartments. But in reality, this "friends with benefits" was not what Katsuki truly wanted.
He knew exactly what he was getting into when he and Izuku first crossed the line. They were supposed to be childhood best friends and rivals, but now everything was complicated.
Was it too late to regret?
Katsuki moved the food from the pans onto their plates. Izuku sat down and smiled up at him. "Ah! It smells so good, Kacchan!"
Katsuki rolled his eyes, trying to hide how much that smile still affected him. "Of course it does. I'm the one who made it."
He sat down across from Izuku, the steam from the food rising between them. For a moment, they looked like a real couple—sharing a meal comfortably in his apartment.
"Itadaikimasu!" Izuku said, putting his hands together. Katsuki did the same thing before they started eating.
Izuku looked so happy. Just looking at him made Katsuki’s heart melt.
Despite the pain, seeing Izuku’s genuine smile made everything else disappear for a moment. Katsuki watched him take a bite, his eyes lighting up at the taste of the food.
It was these small moments that kept Katsuki felt trapped. He hated how much power Izuku had over him without even trying. He wanted to be angry, and he wanted to regret their arrangement, but as long as Izuku was sitting across from him like this, he couldn't bring himself to leave.
"Do you want to come with me to see Uraraka tomorrow? I'm sure she won't mind!" Izuku said, taking another bite of his food.
Katsuki just hummed, keeping his eyes on his plate. "Nah, it’s fine. You two need to catch up. Take your time with Round Cheeks."
In his head, Katsuki knew it wasn't fine at all. It felt like a physical weight in his chest. But who was he to stop Izuku? He didn't have the right to tell Izuku who he could or couldn't see. Especially her.
"Okay! Thank you, Kacchan!" Izuku chirped, his smile bright and genuine.
Katsuki nodded, focusing on his own plate.
----
"Whoa, whoa!" Kirishima shouted. He raised both arms to show he was giving up as Katsuki prepared a massive explosion.
They were warming up for a mission tonight, but Katsuki was not okay. His head was a mess, and his emotions were out of control.
The reason was what Izuku told him yesterday. Izuku had mentioned that Uraraka and him going in patrol together.
Katsuki felt like he had been punched in the gut. He didn't even know Izuku was planning to have same patrol with her. Izuku hadn't said a single word about it.
Every time Katsuki thought about it, he felt a hot, burning anger mixed with a deep sadness that he couldn't push away.
"Bro! What the hell was that? Are you trying to kill me before the mission starts?" Kirishima shouted. He was panting heavily and looked genuinely worried as he stared at Katsuki.
Why could Izuku do a duo patrol with her, but not with him? When Katsuki had asked Izuku to join his agency and work together, Izuku had said no.
It felt like Izuku was building a life with Uraraka—a career and a romance—while Katsuki was just someone he visited when he was lonely or wanted to fuck.
Katsuki didn't listen. Instead, he blasted himself forward, his palm connecting with the wall right next to Kirishima. The impact made the entire room shake, and deep cracks spread across the concrete.
"B-bakugo? Hey, man... I think we should stop." Kirishima said, his voice trembling. He held up his hands, trying to calm him down.
Katsuki didn't move. He kept his fist pressed against the cracked wall, his shoulders shaking as he breathed heavily.
"Right. We should stop." Katsuki’s voice was raspy and cold, making Kirishima laugh nervously.
"Yeah... we definitely need to wrap it up, man." Kirishima said, rubbing the back of his neck.
Katsuki didn't respond. He let his arms fall heavily to his sides and walked away without saying another word. He didn't look back at the cracked wall or at his worried friend.
Katsuki's mind was spinning. He had always been the one person who stood by Izuku, through everything from childhood to the war. He had offered Izuku a place by his side at his agency—a chance to be a real team—and Izuku had turned him down.
Is he jealous of Ochako? He probably is. Deep down, Katsuki feels like Izuku should be his. But the painful truth is that Izuku doesn't want him that way—not the way Katsuki wants him.
Katsuki realizes that while he has given his whole heart to this, Izuku only sees him as a "fuck buddy."
To Izuku, they are just two friends who have sex when they are need to let out heated steam.
---
"Ochako is so amazing with kids, Kacchan! My students really love her. She even helped them learn how to control their emotions so their powers don't flare up!" Izuku kept talking, his hands moving excitedly as he spoke.
They were lying on Katsuki’s bed. They had finished having sex an hour ago, but since they weren't tired yet, Izuku started talking about his day.
Katsuki just listened. He didn't say anything he just stared at Izuku’s face.
He watched the way Izuku’s eyes lit up when he mentioned her name. It was a look of pure admiration—the kind of look Katsuki wished was directed at him. Here they were, sharing a bed and skin-to-skin contact, yet Izuku’s mind was miles away, thinking about her.
"Then, she even made me a bento! She told me I should eat a lot so I don't lose my energy for my students." Izuku said, his cheeks turning a soft pink.
Katsuki felt his heart squeeze painfully. That small blush on Izuku’s face was like a knife to his chest.
He stayed quiet, watching Izuku. How much longer could he do this? How much time did he have left before Izuku decided to end this? He knew that once Izuku and Ochako became officially together, this—nights, the sleeping over, the closeness—would have to stop.
Izuku would leave him, and Katsuki would be left alone in this bed with nothing but memories.
Every happy word from Izuku felt like a countdown. Katsuki wanted to reach out and grab him, to tell him to stop talking about her, but he couldn't. He didn't have the right. So he just lay there, wondering when the day would come that Izuku would finally say goodbye for good.
----
Katsuki had never been this drunk before. Because of his heart condition, the doctor strictly told him never to touch alcohol. But tonight, he didn't care about his health. He just wanted to stop thinking. He drank until Izuku’s face finally faded from his mind.
The walk from the small bar to his apartment was only ten minutes, but it felt like miles. He swayed back and forth on the empty, dark street, stumbling as he tried to find his way home.
Katsuki chest felt tight—not just from the alcohol, but from the weight of everything he was keeping inside. Every step was a struggle. His vision was blurry, and the world seemed to spin around him.
He reached for his phone in his pocket, his fingers clumsy and numb. He wanted to call someone, but he knew there was only one person he truly wanted to talk to. And that was the one person he needed to stay away from.
He let out a shaky breath, his legs feeling weak. "Stupid..." he muttered to himself, his voice thick and slurred. "Just get home, Katsuki."
A few minutes later, Katsuki finally made it inside. He slammed his apartment door shut and leaned against it. His body swayed, and he almost tripped over his own shoes before he let himself fall onto the couch with a loud grunt.
He stared at the ceiling, the room spinning around him.
"Damn nerd." he muttered.
The alcohol burned in katsuki stomach, but the pain in his chest was sharper. He hated that he was laying here, drunk and miserable, while Izuku was probably sleeping peacefully or thinking about Uraraka.
Katsuki closed his eyes, trying to block out the image of Izuku’s face.
Katsuki really wanted to rip these feelings out of his heart.
---
Katsuki woke up with a pounding headache and a dull ache through his entire body. This was exactly why he hated drinking.
He hate feeling like this.
Slowly, Katsuki forced himself to stand up. He pressed a hand against his throbbing temple. Every step toward the kitchen felt like he was going to slip.
He reached the counter and fumbled for his medicine on the cabinet, and took a glass of water. His hands shook slightly as he downed the pills. The cold water felt good against his dry throat, but it didn't do anything to wash away the memory of why he had started drinking in the first place.
Katsuki needed to get his head straight before his shift started, but right now, all he wanted to do was disappear.
Everything was fine before. Why was it like this now? Was this what they called karma?
Katsuki leaned heavily against the kitchen counter, the cold marble pressing into his palms. He knew what he had done. He had spent years making Izuku’s life a living hell when they were kids. He had said sorry—he had bowed his head, offered his apologies, and tried to be a better man. But was it enough?
Was the universe finally paying him back by making him fall for the one person who would never truly choose him?
It felt like a cruel joke. He had spent his childhood pushing Izuku away, and now that he finally wanted to hold on, Izuku was the one moving on.
His head throbbed, a sharp reminder of the alcohol still in his system, but the guilt in his chest was worse. Maybe he didn't deserve a "happily ever after". Maybe this was just the price he had to pay.
"Dammit." Katsuki whispered, his voice cracking in the empty kitchen. He gripped the edge of the sink until his knuckles turned white, wishing he could just blast these thoughts out of his head.
Maybe you’re wondering why Katsuki let this happen in the first place? Why did he let Izuku touch him that night instead of pushing him away like he used to?
The truth is, he couldn't.
Katsuki had changed. He wasn't that angry, explosive kid anymore. He had spent so long trying to make up for the years of hurt he caused, and he promised himself he would never be the reason for Izuku’s pain again. He knew deep down that if he kicked Izuku out or push him away more. It would create a wall between them that might never come down.
So, he stayed quiet. He let the lines blur because even a "friends with benefits" relationship was better than having no relationship at all. He traded his pride for Izuku’s presence, thinking he could handle the cost.
But as he stood in his kitchen, clutching a glass of water with shaking hands, he realized he had made a terrible mistake. By trying so hard not to hurt Izuku, he had ended up destroying himself.