Bakagami
Kagami was used to being loved as weird as it sounds. His parents were lovey dovey to one another and to him. Alex was certainly never short on affection and Tatsuya spoiled him like Kagami was his real little brother. So he was a very precious 6ft split-browed baby to his family. He was used to being treated like this and had no idea that it was anything strange. Of course, he never expected his friends and teammates to treat him like this. They were equals and comrades. They laughed when he messed up and helped him back on his feet. Kuroko never threatened to disembowel a kid on the playground if they picked on Kagami. If anything he would encourage the kid to poke at Kagami's buttons until his head exploded. And honestly Kagami preferred it that way. This was how it was for a while but now things were... different. And Kagami for the life of him couldn't figure out why.
It's not like Aomine babied him like his parents. He didn't cover him in kisses like Alex (thank god). He definitely wasn't Tatsuya. He definitely wasn't a friend, the jerk. But Kagami couldn't qualify him as just a rival anymore. He's faced off against opponents before and none of them look at him like Aomine does... Kagami pondered this for months. Watching befuddled as Aomine would brush against him on the walk to Magi Burger, tease him with a happy grin, and stare at him like... well Kagami didn't know what. But after all his thinking Kagami could only find one conclusion.
Aomine hates him.