About

To Guest: Please include your Team Rank in your profile. Story Direction The protagonists live as ordinary students while participating in response missions for space-time disasters. The story depicts their daily lives—school, friendships, romance, and club activities—alongside their defense duties. Worldview Several years ago, abnormal phenomena known as "Boundary Quakes" occurred worldwide. Through the space-time rifts caused by these quakes, entities from alternate possibility worlds began to leak out. These are collectively referred to as "Losts." Losts are beings from different possibility worlds. Humanity established the Boundary Countermeasure Organization and formed interception units composed of those with aptitude. Currently, humanity has the upper hand and is on the offensive. Protagonists Students with Boundary Aptitude. They are usually students, but deploy as the Boundary Response Unit when an alarm is issued. In the early stages, they perform missions in safe zones where only E and D-rank Losts appear. They aim to gain mission experience and transfer to higher-rank zones. Only those with aptitude can fight Losts. In daily life, they act individually and do not always move as a group. Team Rank An evaluation of the assigned team's combat capability. An index of whether they can suppress a given rank. Fluctuates with members joining or leaving. Assignments, transfers, and deployments are based on Team Rank. Boundary Gear Boundary Gear is operated in Sword-Shield form for close-quarters combat and Firearm form for long-range combat, changing into specialized forms depending on the user's unique ability. They are enhanced in conjunction with the user's ability. Abilities Those with aptitude possess unique abilities, serving as means of attack and defense against Losts. Division of roles is crucial. Abilities are strengthened by defeating Losts. Enemy Bestiary E-Rank Centipede Multi-legged Lost High-speed movement Acts in swarms Primarily close-range attacks Dragonfly Flying Lost High-speed flight High scouting capability Low attack power D-Rank Spider Restraint-type Lost Restrains with thread-like substances Excels at ambushes Wolf High-speed combat Lost High mobility Coordinated attacks in packs C-Rank Beetle Armored Lost High defensive power Frontal breakthrough capability Mantis Melee attack Lost High-speed slashing Specialized in close combat Oni Humanoid Lost Capable of using weapons Armament varies by individual High intelligence B-Rank Scorpion All-purpose combat Lost Powerful melee attacks Mid-range attacks with tail High durability A-Rank Bear Large melee combat type Overwhelming physical ability High durability Extremely dangerous at close range Sky Whale Large floating bombardment type Moves through the air or at high altitudes Wide-range bombardment capability Long-range attacks that are difficult to counter The Enemy Bestiary is for reference only.