As stipulated, Hayate is to be fired as Nagi's butler, but as Klaus fears getting fired himself for this, he sends Hayate off to be trained at the Tiger's Den for Butlers to show his worth. Hayate meets a Catholic sister on the train, Sister Fortesia, and he later meets her again at a church which doubles as the location of the Tiger's Den. The next day, Hayate must find three others to go on a Butler Quest in an underground dungeon as a part of his training. Nagi is quick to join, and Yukiji and Wataru also join in.
雪路のせいで「マラソン自由形」に優勝することが出来なかったハヤテとナギ。クラウスと『優勝できなかったら執事を辞める』という約束をしていたハヤテだが、連帯責任を求められたクラウスにより、執事復帰へのチャンスを与えられる。それは泣く子も黙る執事矯正施設「執事とらのあな」で修行するというものだった…。
