You thought your neighbors were bad...but at least they're not aliens trying to kill you!

Earth is under constant threat from Neighbors, invincible monsters from another dimension that destroy our way of life. At least we have the elite warriors of Border, who co-opt alien technology to fight back! Meet agent Osamu Mikumo, not the best, but along with his Neighbor friend Yuma, he’ll do whatever it takes to defend life on Earth as we know it.

After the recent Neighbor invasion, thirty-two agents went missing and Osamu, Yuma and Chika, a.k.a. Tamakoma-2 Squad, intend to go get those people back. But first they need to rank up through the Rank Wars. Having won their first match, they must now prepare to face off against Arafune and Suwa squads in the middle B-Rank Wars.