Charon is a mythological ferryman who ferried the dead into the kingdom of dead across the river Acheron and Styx. He only ferried those who had been buried with coin in their mouth. The coin in the mouth was supposed to be a bribe to induce Charon to ferry them to the underworld. Lack of this toll for Charon would lead to a worse fate of isolation on the bank of river Styx for eternity. Wow, money is such a necessity even after death and I thought bribery works only in this world.