Board Thread:Questions and Answers/@comment-25556796-20141019094413/@comment-6697950-20141019100847

How far have you read? Time in Underworld flows at 1000 times the speed at which it flows in the real world, so by the time one day passes in the real world, several years pass in the virtual world. What Asuna has done so far is track down his whereabouts after he was kidnapped, but since he was being treated for his brain damage, there was nothing that she could do to help, especially since she didn't really know what he was doing in the virtual world. However, if you had read the end of volume 14, you would know that the base where Kazuto (Kirito) being treated was attacked. The attack is elaborated in the chapter that you are interested in.

Also, the story of Alicization consists of two sub-arcs. One has already been completed, while the other has just started. In total, the story is a bit more than halfway done.