Former Bone Thugs-N-Harmony member Kamilha Greer, who was dubbed the "Thug Queen" during her stint with the rap quintet has filed a $22.5 million lawsuit against the group and both Mo Thug Records and Ruthless Records for unpaid royalties.

According to court documents, Greer claims that she was unpaid for her work on Bone Thug's 1998 album, 'Mo Thugs Family Scripture Chapter II: Family Reunion,' which was a collaborative record between a number of artists under the Mo Thugs Family umbrella.

Greer claims that her work includes lyrical contributions to the tracks, 'The Queen,' 'Otherside/Outro,' 'Mighty Mighty Warrior,' and 'Ghetto Cowboys,' the album's hit single, which climbed to number one on U.S. rap charts. The 1998 album sold more than 1 million copies, but Greer said she has not received any royalties, despite appearing in 'Ghetto Cowboys' video. The Ohio native has cited counts of negligence, fraud, breach of contract, Conversion and Breach of Fiduciary Duty as grounds for her $22.5 million request.

While Bone Thugs gears up for this new court battle, the group is still tangled up in legal trouble with Songster LLC, the music company that filed a lawsuit against them in July for copyright infringement on their collabo track 'I Tried,' with Akon. The single was the first release from their 2007 album 'Strength & Loyalty,' and it climbed to No. 6 on Billboard's Hot 100 chart before Songster accused the group of ripping of 1970s song to create the track.