Oikawa has a silly way of showing he cares. He likes to give Hajime candy, the little bugs he collected, his favorite things. His 'treasures'. The things he loved. And Hajime accepts them, because why not? Oikawa likes it and he likes the things Oikawa likes. He loves the things Oikawa loves. "Ushiwaka-chan, you know I love you, right?"