au where kageyama is an android that was specifically designed to be excellent at sports, but he was a prototype that sorta failed and he refused to play anything but volleyball. so his creators retired him to live as a basically normal person, with a surrogate family, so he goes to school and plays volleyball for fun.
but like, being a robot with incredible power and accuracy means he’s 10x better than humans at the game and their lack of reaction time frustrates him, so it’s like canon in that he’s known for being difficult and impatient.
he keeps his android status on the DL, because his design makes him look very human and he can eat for appearance’s sake (he can’t taste the food but the sensation of eating is psychosomatically comforting, so he enjoys it a lot). and it’s not until some match with karasuno that he malfunctions, and he needs external help to fix it, and the only person he can ask is hinata.
he likes that hinata is the one human who can match his speed and skill, but hinata is kind of a dumbass so trying to articulate what to do to fix him with a busted speech processor is DIFFICULT TO SAY THE LEAST, but hinata like. doesn’t mind at all that kags is a robot, he thinks it’s cool.
so he has to reset a panel and kags is printing instructions on a screen mounted inside his chestplate and when he hecks up kags just prints “ボッケ!” (bokke!) over and over on the screen and they fight but it’s like. an affectionate fight. and ever since then hinata helps him with all things electronic and asks him questions.
and very badly tries to hide this fact from the others.
(they think they’re dating.)
(…they’re not wrong per se.)