The Bloodwritten Clue

Riddle: A man hosted a party and invited 25 people. Everyone was having fun—eating, drinking, dancing, and some were playing games. Suddenly, the host vanished. People searched for him and eventually found him dead in his room. They called the cops, and when the investigation began, they discovered that the man had written a name in his own blood before dying: “Frank.” Among the attendees, the police initially focused on five suspects: Francis, Roman, Amanda, Nji, and Kelvin. Who killed the host?