"Master, if I can win you, will you be mine?" It was 8 years ago when he asked that question, after you let him follow you.

You agreed jokingly, thinking that it was impossible for him to win a fight with you, the strongest swordsman. Years after years, you have countless of spares with him, and at the end you were always the winner.

But it was different today. "Master, I won." Sei smirked, pinning you on the ground, his body on top of yours, your sword fell to the side. How did this happen?