Chris Brown & Rihanna

The mystery blonde who's been accused of destroying Chris Brown's relationship with Rihanna isn't exactly a threat ... because she says she prefers vanilla over chocolate.

22-year-old Keisha Kimball -- a waitress at L.A.'s Playhouse nightclub -- was photographed holding CB's hand last Saturday inside the club ... and now she's being blamed for Chris and Rihanna breaking up.

But Keisha tells TMZ, “I am always Chris’ waitress. I know him and am friends with his friends. Nothing has ever happened. I just work there. In the photos, he was handing me a bottle to drink out of. Of course people are going to twist it another way. I don’t go for black guys."

Keisha -- who says she's not racist ... it's just a dating preference -- adds, "Whatever is going on between Rihanna and Chris Brown is between them. I’m not trying to be a home wrecker."

And get this ... Keisha says CB is normally a great tipper, but last weekend he stiffed her ... in the gratuity department of course.

As for the CB/Rihanna breakup rumors ... our sources say they're true ... but it's nothing out of the ordinary for the on-again-off-again couple.

It took Chris Brown 23 years but he's finally done it -- he's learned that hitting women is a bad thing!

CB sat down with Matt Lauer on "Today" this morning and actually opened up about his relationship with Rihanna, rather than throw a chair through a window when asked about it.

"As far as me and her are concerned," Brown said ... "She knows my heart and I know her heart. I'm not really focused on the negative, everything about it is positive for me. I did my 52 weeks of counseling and learned that it was absolutely wrong."

So that's a 23-year-old man ... having to learn that beating the living crap out of a woman ... is wrong.

Chris Brown is backing off last week's proclamation that he is sole and rightful owner of Rihanna's lady parts ... telling TMZ, "It's a song ... it's a song ... that's all it is."

Brown was leaving Lure nightclub in L.A. this weekend when we brought up the statement he made at the Emerson Theater last week ... when he gave the crowd a quick lesson about how to talk to women.

"You GOTTA say that one thing to her," Brown said ... "Don't make me have to tell you again, that's my p***y baby! ... so you better not give it away!"

But on his way out of Lure, Brown was playing it off as if it were only a joke ... so we joked back.

Chris laughed ... it was kinda funny. Check out the clip.

Chris Brown has a message for Rihanna ... and any other guy who might want a piece of her ... back off, because "THAT IS MY P**SY!"

Chris was partying at Emerson Theatre in Hollywood early Thursday AM when he grabbed the mic from the DJ and went off on how to talk to your woman -- and the bizarre rant was all caught on tape.

Chris said, "You GOTTA say that one thing to her ... Don't make me have to tell you again, that's my p***y baby! ... so you better not give it away!"

Chris rambled on ... "So every person in this motherf**king building, if you got a bad bitch you better say that s**t to her, or she might f**k another n***a."

Another girl tip ... don't beat your woman.

Rihanna's controversial reunion with Chris Brown will end with him killing her -- at least that's the way the writers of "Law and Order: SVU" see it ... based on last night's explosive episode.

This had to be the easiest script the 'SVU' crew ever wrote ... as it copied the Rihanna-Chris saga almost exactly -- and simply changing the names to Micha and Caleb.

The first brutal domestic violence incident goes down as Micha (Rihanna) catches Caleb (Chris) hugging another woman, and says ... "Caleb, I can't leave you alone for 5 minutes without you getting trashy."

Caleb (Chris) says "Who you steppin' to?" -- then yells, "Skinny ass whore!" ... as he slams her head to the ground and punches her in the face.

Just like real life ... Micha (Rihanna) refuses to testify against Caleb (Chris Brown). The 'SVU' detectives even say at one point, "They should go on a double date with Chris Brown and Rihanna."

But the ending seemed to be ripped from a different scandal.

Caleb (Chris) and Micha (Rihanna) are having a romantic moment on a private yacht when she asks about a text message on his phone. Caleb (Chris) says, "Haven't you learned to mind your own business?"

The next scene is a reporter at a memorial for Micha (Rihanna) ... whose body was found in Bermuda ... floating next to the yacht.

Chris Brown is calling the infamous Rihanna beating in 2009 the "deepest regret of my life, the biggest mistake."

Brown told the UK Mirror, "Sometimes you row, you fight, with the one you love and things get said, stuff spirals."

He added, "But she loves me -- what can I say? I’m forgiven ... but, yes, I worked hard for it.”

You'll recall, Brown infamously brutalized Rihanna on the night of the Grammys back in 2009. He pled "guilty" to felony assault following the incident and was sentenced to probation and community service. He and Rihanna are now officially back together.

Rihanna turned 25 years old yesterday ... and she celebrated by throwing on one of her smallest bikinis and hitting a jet ski in Hawaii ... with Chris Brown.

RiRi and Brown spent the whole day together ... holding hands, jetting around in the ocean ... and probably smoking weed.

Rihanna capped off a night of partying in London with a bloodied knee after someone allegedly threw a bottle in her direction ... and screamed things at her about Chris Brown.

According to reports, RiRi was leaving a club called The Box when someone threw a bottle of Lucozade (a UK energy drink) in her direction. The bottle didn't connect, but Rihanna allegedly scraped her knee during the commotion when she brushed up against a metal shop grate.

Rihanna was in town for London Fashion Week.

We reached out to a rep for RiRi -- so far, no word back.

The way to Rihanna's heart ... is through her lungs ... 'cause the pop star says she got a WHOLE LOTTA MARIJUANA for Valentine's Day ... and she's totally stoked.

Rihanna posted her V-Day haul on Instagram ... along with the message, "Roses are green! Somebody knows how to make me happy."

The question is ... who got her the gift???

We already know Chris Brown has a California weed card -- so he can buy for HIMSELF in CA -- but it's against the law to buy pot for somebody else.

The police chief who signed off on Chris Brown's alleged community service has resigned.

Bryan Norwood, Chief of the PD in Richmond, Virginia, was intimately involved in certifying Brown's community service hours -- hours the L.A. County D.A. claims were never performed. Norwood was instrumental in removing Brown's case from the Richmond Probation Dept. and placing it squarely in his hands. Norwood also wrote a letter to the court vouching for Chris ... claiming all of his community service had been performed.

The Mayor of Richmond says his office and the Chief reached a "mutual agreement" for his resignation.

There had been speculation for weeks the Chief might have resigned to get a similar job in Raleigh, North Carolina, but the buzz in Richmond is that the Brown scandal accelerated his decision.

The judge in Brown's Rihanna beating case wants Brown to verify his hours. If he can't, he's in big trouble and his probation could be violated.

Chris Brown had another Grammy weekend filled with drama -- but at least no one was arrested this time ... or beaten. Baby steps.

Rihanna and Chris Brown's new romance has already gone to pot -- the couple celebrated CB's zero Grammy wins by hitting up a Hollywood nightclub last night ... and lighting up what appears to be a joint.

Chris and Rihanna -- who won her 7th Gram last night for her "We Found Love" music video -- dropped by Supperclub for a private party ... and according to sources inside the venue, the whole place was filled with pot smoke.

It's the first time the couple's been together on Grammy day since 2009 ... and we all know what happened then.

And there's this -- Chris was shot driving away from the club with Rihanna in the passenger seat at around 3:20 AM ... which would be a big issue if he's driving under the influence of pot -- a big issue because he's on probation for beating his passenger to a pulp.

Chris Brown and Rihanna got nice and close during Sunday night's Grammy Awards.

Fresh from wrecking his car yesterday, Chris Brown showed up the Grammys -- without Rihanna at his side -- and proved he's got a lot of nerve ... to wear an all white suit.

Chris Brown is on the hot seat after the L.A. County D.A. filed legal docs claiming he phonied most of the community service he was required to perform in the Rihanna beating case. So we gotta ask ...

The man who could have been the key to Chris Brown's demise is not entirely backing the District Attorney ... saying it's possible Chris waxed the floors at a Virginia Children's Center as part of his probation even though he never saw it happen.

TMZ spoke with Neil Cobb -- who says his statements to the media were taken out of context when he was quoted as saying, "Chris never helped me do floors at the Tappahannock Children’s Center."

Cobb says Chris never cleaned the floors IN COBB'S PRESENCE ... but it doesn't mean he couldn't have done it some other time.

"He mighta did floors ... but he didn't do it with me," Cobb said ... adding, "I never said the guy didn't do his community service."