Lillian, originally called Drox Chemical, Die, and Munitions, is the corporation that bought Cheers from Sam Malone after his aborted wedding to Diane Chambers. They made Rebecca Howe the manager of Cheers.
Robin Colcord eventually used Rebecca's computer to attempt a hostile take over of Lillian to give it to Rebecca as a gift. In order to keep Rebecca for getting arrested for insider trading, Sam told them about Colcord's intent, with the evidence he shredded. Colcord was arrested. To repay Sam for giving them Colcord, they sold Cheers back to Sam for $1. He didn't quite get enough money, but they took it anyway. Shortly after that, Lillian fired Rebecca.