Jabu was the Monoceros saint of the XX century.
Jabu is not a villain in this tournament, being only a competitor. He defeated Ban, but was defeated by Shun, and was too injured to fight against Ikki and don't become one of the 5 main bronze saints, get secondary importance.
Jabu and Ichi serve Artemis after Athena gives the Earth for her. But, is not known if he was a loyal service to Artemis.