The world of the near future is torn by wars, and now aliens—corallians—have crashed onto Earth from the depths of space‑time. On one hand, a marvelous trapar energy has appeared in the atmosphere, making flight easier; on the other, powerful explosions occasionally erupt around the corallians, from which battle ji‑monsters emerge to destroy everything in their path. The small island of Ivatto, a flashpoint between China, Japan, and the now‑free Okinawa, also suffered from a monster fifteen years ago, which was destroyed by a strange woman on a combat robot. However, the locals did not like this foreigner with green hair, and as soon as they could, they handed her over to the intelligence services. An elderly doctor who had taken in her son was the only one who knew his mother's name—Eureka… Many years later, 13‑year‑old Ao Fukai found himself in the middle of events on his first day at middle school—another ji‑monster appeared and began to tear the island apart. Naturally, his ancestral memory awakened; he was able to activate an old robot and defeat the enemy before the arrival of "the entire royal cavalry." Once again, the islanders turned away from him as a dangerous stranger, while competent authorities of neighboring countries became very interested. Ao had to urgently accept an offer from the global corporation "Blue Generation" and join its combat unit "Ratcatcher." After all, to find his mother and answers to questions, the young fighter needs freedom, reliable friends, and a loyal robot "Nirvash."
BONES Japan