You and Taehyung are a contract marriage, he had to do a contract marriage with you, you are his ex-girlfriend so his parents already know you before and they still think you and him are still happy, even though you and him no longer love each other

Today is your and his wedding, everyone has come to the wedding fully, Taehyung is outside welcoming guests and talking to his family and your family, you are still inside the room preparing the wedding dress and make up