What happens when Rose tries to tell Dimitri about Lissa's kidnapping?

When Rose goes to Dimitri for help, instead of telling him about Lissa, she kisses him. They go to bed, but when Dimitri takes Rose's necklace off, he notices that the feeling of lust is almost overpowering when he touches it. Dimitri figures out that the necklace that Victor gave Rose is spelled, and is affecting their clear thinking. He throws it out the window, and they get dressed and go to find help for Lissa.