The Head of Janus was created on 1920-08-26.

He had two faces, one on either side of his head.

Janus has two heads and one head is like mean and the other is nice but they both try to fool you. its in book 4 of the Percy Jackson series

The roman name for janus is also janus

Janus is an ancient Roman god of doorways, of beginnings, and of the rising and setting of the sun, usually represented as having one head with two bearded faces back to back, looking in opposite directions.