Although there are plenty of no-brainer duh reasons why you shouldn’t get romantically involved with a coworker, office hook-ups are laughably inevitable. For one, spending at least 40 hours a week with people begets very close relationships — many that ascend to intimacy. Others who fall victim to work romances develop affinities for nurturing bosses and mentors in powerful positions, confusing admiration for a crush. Then, there are the folks who simply want to engage in fun trysts, given the convenience of the situation.While some companies have guidelines against in-office romances, following the rules can be impossible, especially when the sexual tension is too much to ignore. And to be fair, it’s not all bad — according to a 2011 Career Builder study, about 30% of all workplace romances lead to marriage . But for every success story, there are many more that end in regret. Ahead, we rounded up 10 true tales of workplace romances that might have you thinking twice before you proposition your office crush this Valentine’s Day.