The Try Fighters have won the West Tokyo qualifying tournament for the Gunpla Battle Japanese Championship. As Sekai recovers from the damage of assimilation, he thinks ahead to the powerful new opponents gathering at the national tournament. Meanwhile Sekai's sister Mirai Kamiki, who works as a fashion model, has been signed up for the "Tokyo Gunpla Collection," an event meant to fuse Gunpla with fashion. The highlight of the event will be a Gunpla Rally between modeling agencies. With the help of Sekai and Yuuma, Mirai successfully builds her Mama-Beargguy. On the day of the Gunpla Collection, Sekai and the others go to visit Mirai after the glorious fashion show. Here they encounter TAKU, the leader of the popular rock group SGOCK Third Generation. Somehow or other, thanks to Sekai, Mirai may now have to go on a date with TAKU depending on the outcome of the race.