Karen Kohiruimaki’s college life in Tokyo hasn’t been as she had hoped, due to her insecurity about her height. She comes across Gun Gale Online and, as LLENN, she becomes known as a “player killer.” But then, another female player aims a gun at her…

The second Squad Jam is about to take place. This time, Karen’s friend Miyu Shinohara will participate as well. She converts her character from another VRMMORPG and starts Gun Gale Online as Fukaziroh. LLENN takes her to go buy weapons...

The teams that have come together to defeat Pitohui’s team, PM4, begin their attack. Meanwhile, LLENN and Fukaziroh head to PM4’s current position. They take the shortest route through the dome before them, but realize there are three enemy teams inside.

The climax of the second Squad Jam begins. With the defeated rival team members and the audience watching, the confrontation between Llenn, Pitohui and M starts.

SJ3 has finally begun. The battlefield is located on an island surrounded by the sea. The word "UNKNOWN" is written on a small hill in the middle of the island. "Is this 'UNKNOWN' the 'special rule' for this battle?"

LPFM managed to defeat many members of the allied enemy team, but the island continued to sink, drastically decreasing the physical space they could move around in. LLENN and her comrades avoid areas near the sea and whip up a plan to cut across the northeast section of the island where members of the allied team have gathered. Clarence joins the allied team at this time. She suggests splitting the team into smaller groups of two people and launching waves of attacks against LPFM. However, immediately after they launch this plan, she betrays her teammates and attacks them. In addition, Shirley, who left the KKHC to fight alone, begins joining in on the attacks against the allied team!

Clarence and Shirley defeat and destroy the allied team. KKHC is wiped out after the two kill each other in a fierce battle. Meanwhile, LPFM rides a truck inside a freight car and calmly heads over to UNKNOWN as if going through a deserted field.

The organizing team of the game announced a shocking, special rule to be implemented. One “betrayer” will be selected from the six remaining teams to form a new team. Pitohui is selected from LPFM, and the team leader of SHINC, Eva, also joins. With this new rule implemented, Pitohui is happy that she can fight against LLENN. Eva gracefully leaves her team, hoping to fight against LLENN, too. All of the "betrayers" meet up on a luxury cruise ship set up in UNKNOWN, forming a most intimidating team named "BTRY"!

LLENN and her comrades head to the center of the island, where they find the luxury cruise ship. As the island continues to sink, they must get on board. However, they can’t carelessly approach the vessel as BTRY awaits them onboard.

It turns out the true "betrayer" from LPFM was LLENN. Pitohui lied, saying she was the betrayer to fight LLENN with all her power. LLENN becomes outraged as she learns the truth and declares she wants to defeat Pitohui.