A terse individual, Fenviel preferred to speak in one-word sentences whenever possible; he also carried a riding crop at all times. In The Winter Knights, he used the crop to hit Vilnix Pompolnius after Quint inadvertently revealed to him Vilnix's mistreatment of his prowlgrin. Hax Vostillix used this incident as an excuse to purge Fenviel from the Academy, because he had put the life of a creature of the earth ahead of that of a sky-scholar. After that, Fenviel spent most of his time hanging around the East and West Landings, observing the abuse of the prowlgrins and giant fromps there but powerless to intervene.
During the battle between the academics-at-arms and Gatekeepers at the Knights Academy, Fenviel Vendix freed the giant fromps and unleashed them on the battlefield, turning the tide against Daxiel Xaxis and his army.