You'll probably end up sleeping with a co-worker. The unnatural barriers you set up to keep things "strictly professional" are just cannon fodder for fantasy and, while at work, you're impervious to your girlfriend's watchful eye. It sounds fun, but Based God help you if things end badly. It's hard enough to shake a love-scorned ex when they don't know your phone extension. Multiply the difficulty of your escape plan by the square root of 1000 grief-stricken Taylor Swift songs if you break a co-worker's heart. Quarterly review spoiler alert: "Doesn't follow through on promises."