Earlier today, we reported that Rihanna and Chris Brown are hooking up ... according to one tabloid. Well, there's a new twist, and its name is Karrueche Tran.

Us Weekly claims Brown, 22, and Rihanna, 23, have been hooking up in secret for nearly a year, despite his present relationship with model Tran, also 23.

Chris Brown and Karrueche Tran were spotted together as recently as January 12, when he escorted his love to a hair appointment in Pasadena, Calif.

If Rihanna's driving a wedge between them, they're not showing it. Publicly.


Still, Tran is fully aware of his cheating, Us swears, and suspects she knows the locale: "Karrueche thinks Chris' studio is where most of the hookups take place."

She's determined to hang onto Brown despite the presence of the "We Found Love" singer. According to a source, Tran "won't give him up for a few discretions."

Warns the first insider: "Chris is a really passionate guy. He's still a hothead and he does what he wants. He'll go off the grid and she'll wonder what's going on."

"But, at the moment Chris and Karrueche are still a couple."

For the record, Brown's rep denies any rekindled romance with Rihanna. "He and Rihanna are just friends," the rep said. "He's not cheating." So, there's that.

In any case, Karrueche, or Kae as she's often called, is a model, "but she also wants to get into the fashion world more," an alleged insider explains.

"She definitely chased Chris, and it worked! He was really into her in the beginning and still is. He tells her she's so very beautiful all the time."

He's not wrong. Or stable or faithful, depending on what you read.

[Photos: WENN.com]