Blazblue (series); currently playing Blazblue Chronophantasma - Kagura Mutsuki
Marvel vs. Capcom (series); recent, III - main: Strider Hiryu (*replaced by Deadpool), sub: Super Skrull
Vampire Savior - main: Dimitri, sub: J. Talbain
Soul Calibur (series); recent, SCV - main: Taki (*replaced by Natsu), sub: Mitsurugi
Sengoku Basara -Motochika Sasakibe
Ultra Street Fighter IV Arcade Edition - main: Yun, sub: Yang
King of Fighters (series); recent, XIII - main: Iori Yagami, sub: Joe Higashi
Street Fighter x Tekken - main: Law, sub: Abel
Guilty Gear (series); recent, GG^core - main: Ky Kiske, sub: Chipp Zanuff
Tatsunoko x Capcom II - main: Tekkaman Blade, sub: Karas
Capcom vs. SNK (series) - main: Iori Yagami, sub: Athena?
Samurai Shodown (series) - Haohmaru, Haohmaru, Haohmaru
Killer Instinct (series) - B. Orchid, Sabrewulf (duh)
Bloody Roar (series); recent, IV - main: Bakuryu II, sub: Yugo/Nagi
Melty Blood (series); recent, Tsukihime - main: Ciel, sub: Shiki Tohno
Persona 4 Arena - main: Akihiko Sanada, sub: Kanji Tatsumi
Mortal Kombat (series); recent, Armageddon - main: Kenshi, sub: Scorpion
Skullgirls - Filia
Tekken (series) - Law, Law, and Law; Xaioyu, maybe...
Dead or Alive 5 - Ryu Hayabusa
Dragon Ball Z: Budokai Tenkaichi (series); recent, III - Baby Vegeta
Battle Fantasia - Urs van de Land
JoJo's Bizarre Adventure - Mohammed Avdol
*Super Smash Bros. (series); recent, Brawl - main: Link (¹), Ganondorf (Melee/Brawl), sub: none (¹), Sheik (Melee), Link/Marth (Brawl)
*I still don't consider SSB as a fighting game.
There's probably something I forgot—possibly hundreds...