[Crossover] My Childhood Friend Is the Team Captain

As children: The witch's everyday dilemma: How can I get my little brother to play with me? The proper young master: I'm busy with class. Not interested. And he's not my little brother, he's my fiance. As adults: The witch's everyday delight: A stick and a carrot. That'll make sure my little brother pays attention to me. The elegant young master: ... (I don't want to pay attention to you.) P.S. The story starts in childhood. There are some alternate character interpretations, and the timeline is a mess. Please don't nitpick the details.