Sword Art Online: Project Alicization, Vol. 5 (Manga)

After speaking with Cardinal, Kirito faces many unpleasant truths, and all ofthem lead to Quinella, the Administrator of the Underworld. Her unfathomable power makes her virtually untouchable, but if Kirito wants to have a chance at stopping her, he'll first need to ascend Central Cathedral's many floors with Eugeo. And with Integrity Knights waiting to ambush them around every corner, that's no easy task...