Theo Vormercier was the nephew and presumed heir to Count Vormercier on Barrayar, but the Count remarried and began producing sons of his own, thus reducing Theo's financial hopes considerably.
As he'd been living rather lavishly on expectation of wealth, the loss came as a most unpleasant shock. He and his younger brother Roger (who'd also hoped for future wealth) decided to get back at the system and pay debts by stealing equipment from the Sergyaran Fleet. His schemes ended up running afoul of Imperial Security, who sent Byerly Vorrutyer to investigate the situation.
He owned a rather ostentatious yacht decorated in a manner suitable for wild partying; it ended up being given to the Cordonah family of Jackson's Whole.