Fayaavik was a Jhereg hired by Seodra for various nefarious tasks near the beginning of Tortaalik's reign. He showed an intense concern for his own reputation and honor; he returned gold to Seodra after an early attempt to kill Khaavren and his companions failed.
Fayaavik and an unknown associate are likely the two who accosted Khaavren and warned him not to interfere with Baroness Kaluma.
After Khaavren was released from arrest by the Emperor, he immediately repaired to Seodra's chambers. Using a ruse, he tricked Seodra into revealing that Fayaavik had been paid to assassinate Adron e'Kieron. Pel and Khaavren confronted Fayaavik, and the Jhereg then abandoned the contract.
Fayaavik has not appeared in any of Paarfi or Vlad's other works. It is not known if he was in Dragaera City at the time of Adron's Disaster. Fayaavik is apparently not the same person as Fayavik, a Jhereg who was operating at the time of the events depicted in Dzur.