World Trigger (2014)

When a portal to an alternate realm appears in Mikado City, terrifying creatures known as Neighbors begin to invade. Osamu Mikumo, a dedicated agent of the Border Defense organization, takes up the challenge to protect his home using a specialized weapon called a 'Trigger.' As he navigates this dangerous new reality, Osamu must not only battle formidable foes but also uncover the mysteries of the other world and his own potential. With alliances forming and threats escalating, the struggle for survival intensifies.