Acheron is the name of a river in Greece, which brings the Souls of the dead to the Underworld of Hades. However, over the millenia, the kami of this river has feasted on the Legend of countless Souls passing through it to flow to the Styx. This kami eventually was able to take form, and Acheron could ensure that due respect was given to itself.

Until Hermes, a young Godborn, bathed in Acheron and became a mighty psychopomp himself. Reaching Godhood, the clever God of Messengers organized a network of psychopomps, efficiently finding and bringing Souls to Hades without the need of Acheron to gently guide them. Since then with little purpose, frustrated Acheron has been working as a (under-utilized, in its opinion) cog in Hermes' network.