Finas (pronounced Fin-ehz) is a vampire and Casimiro's long suffering companion. He posesses a calm, even tempered demeanor, though it is clear he would have no qualms with beating the shit out of someone should the need arise.
Finas has only appeared a handful of times, so there is little solid information about him. As of now it is still unsure if he is an antagonist, protagonist, or somewhere inbetween. It has been clearly established however, that he and Casimiro are very much a team despite their polar opposite personalities. They have apparently been together for a very long time (though they didn't meet until after being turned) and seems to have taken on the task of regulating Casimiro's unpredictable temper and impulsivity.
According to scattered bits of information form Tessa, he was originally from England and still retains a bit of an accent. He seems to have no particular love for violence the way Cas does, and is frequently getting him out of the many inconsequential scraps he gets himself into. It is unsure exactly what exactly their relationship entails besides this or even how they met, but they clearly share a close partnership. One can assume that he shares Casimiro's hatred of Adelaide, though he has not openly expressed it in canon.