Once the ladybugs are in your house, they will not eat fabric, plants, paper or any other household items. They like to eat aphids. Aphids are very small, but very destructive pest that feeds on plants. They also prefer a little humidity, but most of the offices are usually not very humid during the winter. In fact, they are rather dry causing most of your ladybug guests to die from dehydration. Occasionally, you might witness a ladybug in your kitchen, break area, or bathroom getting a drink of water.
If you do not have a lot of them, just leave them. They will leave when spring arrives. Disturbing them will only cause them to stress out leaving yellow markings on your walls. The yellow stuff, you see, is not waste matter, but rather, their blood. The ladybugs release a small amount of their blood which is yellow and smells, when they sense danger.