Hardcore otaku Hideki Nishimura enjoys playing a net game with other members of his online guild, and finally agrees to marry one within the game. However, when he finally meets his "wife" in real life, she is not exactly what he expects.

With only one chance to take back Fort Cantor from Wallenstein, Kyo explains her plan to the others of taking and defending the castle until time runs out.

When its members admit that sometimes the line between the game and reality becomes blurred for them, Saito considers the possibility of dissolving the club. The others try to help Ako deal with unwanted attention from her classmates.

Ako asks to play a different game during the club meeting, and Kyoh suggests a first-person shooter. Ako feels threatened when she thinks Nanako is interested in Hideki, and withdraws from both school and her friends.

Having met his other in-game guild members in real life, Hideki begins to picture them in their characters' places. Ako's behavior at school the next day makes it clear that she has trouble separating the game from reality.

During their first club meeting, Akane is delighted by her faster machine, Ako gets a lesson in dressing for the occasion, and Kyoh is prevented from using her premium equipment. However, the line between game and reality becomes more blurred.

Hideki is nervous about revealing his true feelings for Ako before summer vacation. When the first term's final exams draw near, everyone rallies behind Ako, who is in danger of flunking the term, in order to make sure that she passes.

When Hideki is dumped out of his game of Legendary Age and cannot get back in, he soon realizes that his account has been hijacked by someone else. However, before he can do anything to stop them, the damage is already done.

The club members hold their summer club camp at a cottage by the sea, with the provision that for 24 hours, none of them are allowed to connect to the net. The others try to make the camp a memorable experience for Ako.

To persuade Ako to get cracking on her summer vacation homework, the girls have a study session sleepover at Kyoh's gigantic house. However, without Hideki around to keep Ako under control, things soon get out of hand.

The Net Game Club members find that they are obliged to take part in the upcoming school culture festival. However, they are at a loss as to what presentation to make, until Kyoh has an idea that coincides with Legendary Age's fall update.

Rusian and the others include Nekohime and Sette, and recruit the top-ranked PvP guild "Wallenstein" to bolster their ranks. With the additional help, Guild Alley Cats charges in to take over Fort Cantor, but not everything goes according to plan.