I Kept Pressing the 100-Million-Year Button and Came Out on Top, Vol. 3 (Light Novel): The Unbeatable Reject Swordsman

A ROYAL HEADACHE!
When Lia's overprotective father, the king of Vesteria, catches wind of the fact that his daughter and Allen have been rooming together, he abruptly summons the pair back to his domain. There, the king demands that Allen prove himself worthy of Lia by defeating Vesteria's top swordfighters in a series of public duels. After the dust settles, however, Allen finds himself at risk of losing Lia again when a formidable duo from the Black Organization abducts her! Can our hero summon the confidence and power he needs to save his friend?