Machida was an enormous snake-like demon worshiped by the members of the Delta Zeta Kappa fraternity. He dwelled in a chasm in the basement of the fraternity house and fed on young women, as Buffy Summers and Cordelia Chase experienced. Buffy finally killed him by separating him from his snake-like tail with a ritual sword she aquired from the fratboys.
Machida had a humanoid upper body and a long serpentine tail for a lower body, the full length of which remained inside the chasm and was never exposed. His face, most notably his nostrils, had serpentine features. His mouth appeared to be stretchable, and he had pointed teeth. His body was covered with yellowish-green scales. His arms were webbed to his torso. Machida had clawed fingers.
Machida fed on girls offered as a sacrifice by the fraternity in return for immense wealth and protection. The feeding appeared to be done as frequently as possible and did not have a structured cycle.
It appeared that he can only consume virgins, as when Richard tries to abuse a drugged and unconscious Buffy, he was prevented from it by Tom.
In the original shooting script, Machida regenerated from his wounds and confronted Tom. Furious at their failure to sacrifice Buffy, Cordelia, and Callie Anderson, Machida vows never to help the Delta Zeta Kappas again and departs, but not before grabbing Tom and devouring him. Willow later expresses a fear that they will encounter Machida again.
A demon, with a similar head, is present in auctions in "Parting Gifts" .