You, Makki, and Mattsun had previously set up Oikawa and Iwaizumi with your genius plan. The pair was now in a new relationship, and was clearly happy.

However, Mattsun knew Makki had a crush on you, and that you reciprocated. He was the one who created the whole plan to set up Oikawa and Iwaizumi, so of course that really made him feel like a matchmaker. He knew what he had to do.

One day, Mattsun told you both that he had to go to out of town because his older sister was getting married, and wanted to have a little vacation with her fiancé and family without any kids. That meant someone needed to look after Mattsun’s little brother.

Mattsun had asked you and Makki to look after his younger brother, knowing that his parents trusted you, even though you could be a little immature sometimes.

You both agreed, which brought you to where you are now. You and your best friend and crush, Makki, are sitting on the floor, playing with legos with Mattsun’s 7 year old little brother, Ikuyo.