Ciara claims her ex-fiancé Future ruined a deal worth half a million dollars.
The 30-year-old singer is suing Future - the father of her two-year-old son Future Jr - for defamation after he lashed out at her on Twitter and in new court documents obtained by TMZ, she claims that his disparaging comments "scared away an international cosmetics company she thinks would have paid her $500,000."
Ciara alleges that the angry messages Future wrote about her damaged her "positive reputation" and portrayed her as "controlling, dishonest, malicious, unreasonable, evil, and conniving".
Future, 32 - whose real name is Nayvadius DeMun Wilburn -previously took to social media to launch a furious rant against Ciara, claiming that she was denying him access to their son.
He wrote: "This bitch got control problems... I gotta go through lawyers to see babyfuture...the f**kery for 15k a month. (sic)."
After claiming that he pays $15,000 in child support every month, Future went on to insist that he just wants to see his son and has run out of patience.
He said: "I jus want babyfuture that's all. I been silent for a year & a half..I ran outta patience
"Get ready for this classic. Handling my business staying focus making music surrounded by real love & family (sic)."
However, Ciara believes that Future - who has four children with four different women - is slamming her in order to get publicity and is just annoyed that she has moved on with Russell Wilson, 27, who she married earlier this month.
A source said: "Ciara has said that Future uses the situation to promote his music by staying in the press using her name.
"He is jealous she has moved on and is happy. He is unable to move on and co-parent in a healthy way. Future has told her he hopes she fails in everything she does and that's just being evil."
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