A pleasure device (of varying size and shape) inserted into the anus of a male or female who has a busy lifestyle and can't often take time out to seek pleasure with another mammal.
Marie, "I hate my husband, we have three minute sex and he rolls over and goes to sleep. I need more!"
Renatashenae, "I have a buttplug, I get all day sex, multiple orgasms, and intelligent conversation. Wellmaybe the conversation bit is untrue but really, who wants to talk when you can be eating icecream?"