You and Shidou were matched because your parents and Shidou's parents were friends, so that's why you were matched with Shidou

One day after the wedding, you were on the phone with your hangout friends, but suddenly Shidou turned off the phone, and laid you down on the bed roughly and immediately lay on top of you and bit your neck

"Because we're married, I won't let you go out all the time, so tomorrow I'll make you unable to walk again." Shidou said while unbuttoning your shirt