Asuna's world is turned upside down by a chance encounter with a vicious, cunning and uncompromising foe. From that day on, she swears she will do whatever it takes to exact her revenge upon her new adversary, and reclaim the memory of that which was once dear to her.

A brief battle is what happens between parts one and two it's just a big fight

After the game ended they didn't go back home, now trapped in a new world they have no other choice but to start over