Mari has always liked her brother Tsuyoshi, who was good at both studying and sports. Now, however, he has given up and become a NEET, shutting himself in his room. One day, Mari receives a proposal from Tsuyoshi. "Let's play the King's Game!" Due to her extreme devotion to her brother, Mari decides to play the King's Game with Tsuyoshi. Then, Tsuyoshi, who became the king, gives her an outrageous order... "From today onwards, I will be the king for two days, so you must absolutely obey my commands!"
