He Pretends to Be Cool, I Pretend to Be a Loser, and We Both Play Our Own Roles.

"The young master of the restricted zone who pretends to be a loser" and "the best swordsman in the world who pretends to be indifferent" work together to investigate the case, test each other, and become jealous of each other. In the end, they find out - I hid it from you because I was afraid of losing you; you hid it from me because you wanted to protect me. The whole world thinks we have enmity, but only he knows that I love him so much.