Felix Argyle, also known as Ferris, is a supporting character in Re:Zero kara Hajimeru Isekai Seikatsu. He is a skilled knight serving Duchess Crusch Karsten as her personal knight and healer. Felix possesses divine blessings of water and wind, making him an exceptional healer with the rare ability to use healing magic on males. Despite his feminine appearance and dressing in a maid-like outfit, he is biologically male and identifies using masculine pronouns in Japanese. Nicknamed 'Ferris' by Crusch, he has a cat-like personality, often ending sentences with 'nya' and displaying playful, mischievous behavior. Deeply loyal to Crusch, whom he calls 'neesama,' Felix is childhood friends with her and harbors romantic feelings. He is proficient in hand-to-hand combat and uses a green crystal dagger. Introduced during the Royal Selection arc, he aids Subaru and his allies against threats like the Witch Cult.