"After Ryouta Sakamoto is deposited on an island and forced to kill others with unique bombs called BIMs in order to stay alive as a player in live-action 'BTOOOM!, ' he and his newfound ally, Kiyoshi Taira, search for a way off the island. En route, he encounters a heavily armed teenage girl, who, suspicious of his motives, unleashes a vicious barrage of BIMs in his direction. Though initially unwilling to engage, Ryouta decides to fight back. But...

"On a mysterious deserted island, Ryouta Sakamoto, who has been thrust against his will into a vicious game of survival, manages to defeat his first enemy player. While struggling with the guilt of having murdered another person, he stumbles upon Kiyoshi Taira, an older man who fills in some of the blanks about their situation. Ryouta begins to harbor the suspicion that the comapny behind the virtual "BTOOOM!" world is also behind this very real bomber...