|Affiliation||Karlstein, Dorssia Military Pact Federation|
|Occupation||Dorssia Agent, Prince of Dorssia|
|Manga||Kakumeiki Valvrave: Uragiri no Rakuin - Vol 2|
|Anime||Return to Karlstein|
F-sech (エフゼクス Efuzekusu?) was a prince of Dorssia, he was a member of Karlstein and was friends with L-elf, A-drei, H-neun and Q-vier. He was killed by L-elf because he had ties to the old government.