It is unclear why Nikita is left at the bar, after punching the guy and him being retrieved by Section. She returns to the counter, where the annoying man had been trying to pick her up, and finishes the last few drops at the bottom of her glass. There is no way that a smart government agent, such as Nikita, would do such a dumb thing: since she told the man she was returning, he---or anyone else for that matter---could have spiked her drink.