Phenel

Feynail Tsuleu-Arde Corwen (フェーネル＝ツレウアルド＝コーウェン) is a member of the Corwen family, the most prestigious dukedom in the Eastal League of Free Cities, by his marriage to Saraliya. The two have three children together: Risselthea, Rayneshia, and Iselus.

Because Serjiad Corwen, the current Duke of Maihama, had no sons, Iselus will inherit his title. Until he comes of age, Feynail serves as his guardian.

Before the Catastrophe
Feynail came from an earldom in Maihama, and was adopted by his wife's family when he married her. The two met when Saraliya became involved in the world of politics, and she instantly fell in love with him. Since Serjiad has no son, Feynail and Saraliya's son, Iselus, will be Serjiad's successor.

Return of the Goblin King arc
Feynail makes his only in-person appearance during The Return of the Goblin King, when he is informed of the sudden appearance of hordes of goblins that far outnumber the forces of the People of the Land. He tells his daughter to remain at the Ancient Palace of Eternal Ice with her grandfather, while he and the other nobles plan for the coming invasion.

Homesteading the Noosphere arc
Neither Feynail nor Saraliya appear during this arc, despite the focus on Maihama. They are mentioned, however, during one of Serjiad and Isaac's talks, where Serjiad informs the Adventurer that Iselus would be his successor.

Trivia

 * His birthday is August 19.
 * The first season of the anime has Feynail call Duke Serjiad his father, whereas he is Serjiad's son-in-law in the light novel. In season 2, this mistake is rectified after Isaac asks Serjiad about "his son."