Following another split from John Mayer, Simpson parties the night away in West Hollywood. Plus: Kate Hudson, Nicole Richie and more

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BACKUP PLAN

Paris Hilton's pal Kim Kardashian backs up her curve appeal while out for dinner at Koi in Los Angeles on Monday. Recently, Kardashian spoke out about her incarcerated pal, telling PEOPLE: "[Paris] is a smart girl and will be okay. It's all about learning from her experiences."