The man known as Headache was an engineer and inventor. He had light-colored hair and often complained of severe headaches (hence his nickname).
Headache owned and operated a slot machine factory but became disillusioned with his corrupt business and offered to sell it to his partners. They obtained the money for the transaction from Popsie's Mother, who was working for The Slot Machine Ring. Rather than allow Headache to retire, she forced him to stay and work at his factory, under threat of violence.
Headache escaped and tried to kill Popsie's Mother, but was convinced not to by Popsie, with whom he formed a close relationship. The two tried to alter the slot machines so that they would pay out more frequently and cause the Ring lose money.
Headache was captured by the Hardly brothers (operative of the Slot Machine Ring) and was forced to undo the changes to the machines or be fed to their lion. He complied with their demands, but was told that he was still going to be fed to the lion. He resisted and was shot dead.
Headache's body was dumped in a nearby large body of water tied to two slot machines, but it was eventually recovered by the police.