Sylvia is the primary female character, first introduced as Joe's girlfriend. She has light skin, pink lips, and straight blonde hair styled in a hime-cut with swept-back bangs, always wearing distinctive thin, round glasses. Her initial civilian outfit is a pale sky-blue blazer dress; later appearances feature a sleeveless pink V-neck minidress with a black belt, white scarf, fingerless gloves, and heeled go-go boots. She is the daughter of superhero Captain Blue and the twin sister of Goldie, sharing an identical appearance except for her glasses. During a movie date with Joe, an antagonist pulls her through the screen into Movieland, initiating the core conflict. Captain Blue gives Joe a V-Watch to rescue her, casting Sylvia initially in a damsel-in-distress role. After her rescue and reconciliation with her father, Sylvia obtains her own V-Watch, transforming into the superhero "Sexy Silvia" (renamed "Go-Go Silvia" in the English anime). Her superhero costume echoes the sky-blue of her first dress, comprising a skirted leotard with a white V-neck, long gloves, go-go boots, pantyhose, and a matching helmet with a hot pink visor; her hair becomes a long ponytail. As Sexy Silvia, she becomes a fully playable character alongside Joe, utilizing dual guns and a unique combat moveset featuring the "Replay" action. Correctly timing this ability replays an attack sequence three times, amplifying damage and creating electrical sparkles. Her role shifts to active participation against threats like the Jadow organization and Gedow aliens. Her relationship with Joe evolves into a battle couple dynamic, occasionally showing tension over his interactions with females like Miss Bloody Rachel. She also forms a mentorship bond with the younger hero Captain Blue Jr. Beyond the core games, Sylvia appears in spin-offs *Viewtiful Joe: Red Hot Rumble* (playable in civilian and superhero forms) and *Viewtiful Joe: Double Trouble!*. She features in crossovers *Tatsunoko vs. Capcom: Ultimate All-Stars* and *Marvel vs. Capcom 3*, primarily during Joe's "Desperado" hyper combo piloting the Six Machine cannon. Director Hideki Kamiya confirmed Sylvia is the character "Silvianne Lumiére" in *The Wonderful 101*, who wields the "Desperado" weapon. The anime adaptation loosely follows her game arc—abduction, rescue, becoming Go-Go Silvia—but introduces alterations for international broadcasts, including zipping up Sprocket’s jumpsuit and editing gestures from transformation sequences.