I started on this yesterday, but after a day I’m still not entirely sure I can put it into words that make sense. Riko said it right when he warned Neil that Neil would never understand it–there were a lot of layers to Riko & Kevin’s relationship, and the biggest problem was that several of those layers conflicted. Owner & pet, brother & brother, partner & partner. Riko & Kevin never fully understood it, which is why until the day Riko died they still leaned so fiercely on what was familiar ((Kevin to his role as 2nd, Riko to Kevin’s place at his side))

This is probably an incomplete answer, but this is the best thing I can come up with and I’m sorry:

Honestly I’m not sure I’ll be able to answer this, because Riko & Kevin are screwed up and steeped in too much history for me to be coherent anymore, but… I’ll take a shot at it. Because oh god yes, let’s talk Kevin & Riko, my poor babies. They loved each other until they died, and they hated each other from the moment they met.

Did you know that from day 1 of All for the Game, when it was a shoddy little comic taking place in a Japanese high school, up until the second-to-last draft, they were lovers? The main drama in the first comic was that Riko had cheated on Kevin with Jean, and Kevin stormed off in a heartbroken fit, and Riko was trying to win him back before Kevin & Neil fell in love together. Ha! They’d grown up together, after all–it was impossible to think that they couldn’t fall in love with each other and explore their sexuality and obsession together. Unfortunately I had to tear apart their relationship the same time I pried Kevin out of his obsessive relationship with Andrew & Neil.

((I’ve seen a couple comments on how I focus more on A&N when I comment on that threesome, but although N&A had more chemistry and screen time, K&A were far more dedicated to each other and were the source of a lot of insecurity on Neil’s part. Kevin & Neil got into several arguments over whether or not Neil was just a replacement for the boy who refused to give Kevin the time of day. I’ve just left most of that obsessive KxA subtext out of related conversations because there’s not much point dwelling on things that no longer exist.))

Kevin came to Riko & Tetsuji on the tail-end of tragedy–his mother’s untimely death. He was shattered and withdrawn, and being handed off to Riko as a pet was an afterthought because he came as an athlete and Exy was the one thing his mother had instilled into him since the time he could sit still in front of a TV. He clung to Riko the way a weaker power clings to a stronger, needing some sort of support and stability to rebuild his broken life around, and although he feared Riko’s cruelty he didn’t understand at the time how wrong and unfair it was. It was just life, as he knew it, as he’d know it for the next many years.

To say Riko & Kevin were friends seems a lie, but to say they weren’t is a worse one. Riko & Kevin couldn’t be friends because the master-pet mindset was something Riko drilled into Kevin over and over, but they achieved an understanding and balance they shouldn’t have otherwise. In short, Riko & Kevin were the end-all be-all of each other’s existence. It was what saved Kevin from the majority of Riko’s cruelty, but Riko would have hurt Kevin tremendously if he thought Kevin forgot his place.

Exy was the end-goal of everything they wanted, the purpose they built their lives around, but they were so codependent it was ridiculous. From the time Kevin arrived at the Nest to the day Riko broke his hand, they weren’t ever in different rooms. It was something they started in the beginning, when Kevin was trying to recover from his mother’s death and Riko was testing his new position as master of a human pet, but they never grew out of it. It didn’t matter if they were going to practice, to interviews, or to the restroom–where one went the other followed.

I say “where one went” instead of “where Riko went” because the older they got, the more they found a balance neither one of them was 100% willing to recognize or admit to. They needed each other, because the only thing in the world they wanted was to be the best and the only way to be the best was by plunging into life side-by-side. They were obsessed with each other’s potential because they knew what they could be together.

The critical difference was that Riko saw Kevin as a footstool, and Kevin saw Riko as a collar. Riko refused to think Kevin was anything more than a critical means to an end, and Kevin learned that Riko was a threshold he could not ((on pain of death, not on grounds of ability)) surpass. Thea was the first to mention it, the first to ask Kevin does he know you’re better than he is?

It was downhill from there: Thea’s words were validation for the gnawing feeling that sneaked into Kevin’s head no matter how hard he tried to banish it. Because Riko was family, was a friend, was a captor, was his alpha and omega–but the only thing that could really matter in the end to either of them was Exy. And once Riko started to interfere with that, Kevin started to chafe at the restrictions placed on him. Maybe Kevin could have tolerated it for a few more years, maybe not–his will was never put to the test because Riko inadvertently confirmed every desperate suspicion he had by breaking Kevin’s hand.

Kevin would never forgive Riko for that betrayal, but that outrage/grief could only temper his obsession with hate. Kevin & Riko remained obsessed with each other up until the point Riko died. The difference was Kevin learned how to balance his need for Riko with his need to be the best, and the scales finally tilted the way he needed them to.