I think this one needs the rape tag I believe I remember this one from a bad end where that guy suguo rapes her. Yes it is Asunama Soushuuhen. Basically instead of Kirito saving her he gets to brainwash her and she ends up being his digital whore. Kirito is only seen in the shattered fragments of her mind as she thinks she is doing it with him instead of what looked to be random users.