Frumpkin

Frumpkin is a feline familiar of Caleb Widogast. As a magic cat, Frumpkin can appear, disappear, and/or re-appear at Caleb's whim.

Caleb can also take control with Frumpkin, seeing through the cat's eyes.

Trivia

 * Liam shared his vision of Frumpkin on Instagram.
 * Caleb's ability to take control of Frumpkin is similar in function and appearance to a warg on "Game of Thrones".