No, it's not what you think. I'm a busy woman, living in a busy city, trying to balance work, fun and a never-ending struggle to achieve and maintain good health. That means I work a full day, I work out almost every day, I make dinner almost every night, and I try to pack some fun into my weekends to compensate for my crappy job.
In order to facilitate this juggling act, I often find myself stripping down to my skivvies after coming home from a workout and doing quite a bit of prep and/or cooking before I hop into the shower. This way, I can take care of the 'dirty work' of making dinner while I'm still... well... dirty! Don't worry, I wash my hands thoroughly and carefully before food preparation, and I do wear an apron if I anticipate volcanic activity of any kind.
And if you're still curious about the underwear, it's basic black, standard-issue Gap, and boring as hell. Sorry 'bout that!