B'T X

Teppei is headed to visit his older brother Kotaro Takamiya at a scientific conference, a reunion that's been 11 years in the making. However, his plans are disrupted when a woman named Aramis kills everyone at the conference to kidnap Kotaro. Along the way, Teppei stumbles upon a broken mechanical horse called B'T X, which revives after he supplies it with his blood. Now joined by this unlikely ally, Teppei sets out to rescue his brother from the Machine Empire.