Memo to Bachelor Ben Flajnik: Courtney Robertson's much worse than you think!

On Monday's episode of the ABC hit, a few of Flajnik's bachelorettes pulled him aside for a heart-to-heart about the most hated woman in the house.

"We want you to be cautious about Courtney," Nicki told Flajnik during their group date with Kacie B. and Rachel.

Added Kacie B.: "Yeah. Tread lightly."

Their words of caution appeared to come as a surprise to Flajnik, who was also warned of Courtney's crazy ways by Emily. "Until now, all I've heard is that there's a beef between Emily and Courtney," Flajnik said.

Nicki argued that it's not just her feud with Emily that's worth watching. "When somebody really cares about somebody, it's evident in how they speak, and I can't say I've observed that with her," she admitted. "I want you to be happy in the long run and end up with someone who's going to give you 110%."

Indeed, an insider tells the new issue of Us Weekly Roberson isn't really searching for love.

"Courtney fooled everyone in during the casting process. She seemed sweet and normal," the source explains. "But it became clear Courtney came on the show to win. It wasn't about Ben or finding true love. She just wanted to be famous."

As the season -- which taped its finale last November -- plays out, a second source says Flajnik is becoming dismayed as he watches Robertson's scheming on TV.

"It really bothers him," says a pal. After proposing to Ashley Hebert last year and being rejected," Ben once again feels like he was fooled," says his friend. "He figured that on The Bachelor, he would have more control of the situation, but he had the wool pulled over his eyes by a few of the girls and feels like a loser again."

The Bachelor airs Monday at 8 p.m. (EST) on ABC.