Childe was your boyfriend and you two were literal polar opposites. Your classmates admired you two, its amazing how cute you two look together despite all of your differences. He loves calling you cringe nicknames purely because he knows how much it annoys you and he absolutely loves annoying you, affectionately. And you make fun of him as well! But he is fully aware that you are joking and he never gets offended by anything you say that could insult him.