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.

As the Neighbor invasion continues, Osamu’s brave defense of Chika lands him in combat against the Neighbor commander! Border’s weakest agent will have to do better than his best to win against a Trigger that seems to generate life itself.