Stephanie Grimaldi is a drama/thriller/supernatural Episode story, written by Stephanie Mengle. It follows the story of Steph, the main protagonist, who lives in California with her best friend, Selena; her best friend's boyfriend, Matt; and Steph's childhood sweetheart, Mason. Things begin to change for Steph when the demon-brothers, the Drakes, walk into all their lives. Steph's life is also changed forever when her demon soulmate, Steffan, walks in to her life.
- Stephanie "Steph" Grimaldi - main protagonist who submerges into the demon lifestyle of her soulmate, Steffan Drake.
- Steffan Drake - Steph's soulmate, demon, and son of Lucifer. Steffan changes Steph's life when he enters it. Steffan is notibly the honorable one out of all his demon brothers, which Steph learns to admire.
- Collin Drake - Steph's demon best friend, lover, and son of Lucifer. He originally has little regard for human life, until he falls for Steph.
- Selena - Steph's childhood and current best friend, roommate, and is often a source of advice for Steph (whether she wants to hear it or not). Selena is also a vampire.
- Matt - Selena's boyfriend and childhood sweetheart, he is also Steph's good friend and also a vampire. He becomes with the demon lifestyle as Steph begins to fall for Steffan.
- Mason - Steph's first love and childhood sweetheart. Steph breaks up with him when she begins to fall for Steffan. However, Steph and Mason continue to love each other and support each other as close friends. Mason is often another source of advice for Steph when Steph's best friend, Selena, isn't there for her.
- Daniel Drake - the eldest Drake, demon brother, originally seen as the a bloodthirsty demon with little regards to human life. Daniel wishes to earn his role as the superior brother, by Lucifer, his father.
- Aiaden Drake - another demon brother. He can be seen as most like Steffan being he works as a doctor with humans and uses blood bags as a source of food most of the time, not humans.
- David Drake - One of the Drake brother and can be seen as the more violent, bloodthirsty demon brothers. David originally had no regard for human life and saw humans as a source of food and pleasure. He also begins to ruin and mess with Selena's life, until Steph grew closer to Steffan.
- Lucifer - father of the Drake brothers, ruler of hell, and one of the antagonists to this Episode story. He recruits Steph to fight for hell against heaven.
- Nate Humphrey - Steph's on-and-off abusive husband who later becomes a demon and settles with being friends with Steph.
- Sarah - Steph's antagonistic half-sister who looks to mess with Steph at every turn, especially when their lovers are concerned. Sarah is envious of Steph because she marries the love of her life (Nate), despite being married to a man named Henry.
- Claire - Sarah's friend who despises Steph and had affair with Nate long before his relationship with Steph.