Kouichi Hayase has had a lackluster life, plagued by bullying and daydreaming. However, an unexpected incident disrupts his dreary existence when a girl and a colossal robotic entity named "LINEBARREL" are bestowed upon him. The incredible power that Kouichi now possesses throws him and his surroundings into a tumultuous journey full of conflict, mystery, and lasting relationships. Along this enlightening path, the teen encounters fresh acquaintances, says goodbye to old ones, and faces the harsh realities of life as he assumes greater responsibilities.