Sword Art Online. Vol. 22. Kiss and Fly

The day before. While progressing through SAO, Kirito proposes to Asuna, and they decide to spend their honeymoon in Aincrad. But when they arrive at the place where they expect to find their new home, they can't believe their eyes...
The... day later. Since Asuna started using a new character in ALO, she is constantly tormented by mysterious bouts of alienation, the source of which lies in one of the tragedies of SAO...
The Rainbow Bridge. Kirito and his friends have successfully survived the journey to the underwater temple. However, the mysterious dialogue between the lord of the seas Leviathan and the lord of the depths Kraken calls them to a new adventure!
The Sisters' Prayer. The tragedy of SAO has not yet come to an end when one girl agrees to become a subject in the trials of the Medicuboid, a full immersion medical device. Thus begins the story of Yuuki, the Absolute Sword.