For most guys, a great sense of humor in a woman ranks right up there with a nice rack. But some material is no laughing matter. So while it's cool to clown around, stay away from these supersensitive topics. 

1. His Future Hair Loss With the exception of Vin Diesel and a few others, most guys with shiny chrome domes are not deemed the sexiest men alive. That's why many guys stress about potential future loss. And if there's even a hint of thinning, it's certain to be a really sore subject. 

2. His Paltry Paycheck Yes, it's a little Stone Age, but many men still like to think they can bring home the bacon. When their salaries don't stack up, they may feel emasculated. So while you may find it funny to joke about your sugar-mama status, it's not exactly the idea of good stand-up comedy to your guy. 

3. His Mom He's allowed to goof on his mother's muumuus, burned Bundt cake, and obsession with dancing with the stars---but when you chime in, it's a different story. Guys find it disrespectful for girlfriends to rip on their moms. 

4. His (Lack of) Height Ever notice how guys tend to add about two inches to their height when asked how tall they are? That's because they're sensitive to the notion that tall people tend to have more power. Plus, if you make him feel like he's small outside the bedroom, he might wonder what you really think about, ahem, his other physical attributes. 

Ladies!  What is a topic that should never be brought up or joked about with a woman?