Jaco was a baker whose entire family were killed by Izel and her Shrike, resulting in Jaco joining up with Sarge's Squad on a mission to kill Izel. Jaco was then convinced to betray his leader by Yo-Yo Rodriguez after witnessing Sarge murder Pax. Jaco sacrificed his life onboard the Lazy Comet with an Atom Bomb, while he believed he had killed Izel and her Shrike in the explosion.