Butter bugs were a genetically-engineered species of insect designed to produce a food called bug butter. They were invented by Enrique Borgos and marketed on Barrayar by a business owned by Mark Vorkosigan, the twin clone brother of Miles Vorkosigan. Dr. Borgos unfortunately was interested in substance over style and his butter bugs were visually repellent, leading to considerable customer resistance. The redesign by Ekaterin Vorsoisson proved far more appealing to the public.