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.

Having fought their way into the top B-Rank group, Tamakoma-2 gets to battle it out with the big boys for a chance to make A-Rank. Can this squad of rookies win against seasoned veterans who are nicknamed the "A-Rank Reserves"?