Man Up Your Bathroom

Lasers

It can't be your bathroom if it's not really yours, and it's not really yours unless you can defend it from those who would rip it from your clawed fingers.  It should go without saying that the best possible way to do this is any way that involves the use of lasers, but what we specifically want is an impenetrable web of lasers powerful enough to burn through human flesh instantaneously.  Some sort of plasma grid would also be acceptable.  If you need to save money, just make every other bar in the grid either a laser or plasma bar.  The remaining bars can simply be holograms.

Fart Scented Candles

If there is ever a dead giveaway for a womanly bathroom, it's the constant foreign aromas spewed forth from candles, incense, perfume or any other masking agent.  To render your bathroom immune to such unnatural banes, burn candles that smell like what a bathroom should smell like:  farts.  According to my math, any guest's perfume will be nullified by the candle alone, leaving your natural aromas to waft freely.  Save yourself a trip to Linens 'N' Things and make your own.

Actual Sandpaper

Since you're a living human, you've heard the expression that people use when a toilet paper is particularly rough.  "Man, I don't want to shit in the post office," your friend has told you. "Their toilet paper is like sandpaper."  Avoid that awkward, cliched exchange for those you allow to use your bathroom by replacing all toilet paper with actual sandpaper.  Not only will it toughen you up (to the point where you will be able to legally brag about your time in prison), you'll be able to taunt your guests as they exit with calls of, "Awww, was it just like sandpaper?"

A Hose

What were you thinking?  A sink?  Why, so you can wash your panties in it?  A toilet?  So you can flush away your shattered dreams (and dead goldfish)?  Put away your ostentatious bathing habits and grab the one tool you need to steer the fungus away from your man cans.  Also, since your bathroom should be a blank cube of white tile, the hose will allow for easy clean up from anything that might go haywire when you prove yourself too manly for your toilet to contain.

A Kegerator

There isn't a room that couldn't be improved by the addition of a Kegerator.  There isn't a three feet by three feet area which wouldn't be bettered by a Kegerator, including those which already contain Kegerators.  If you didn't know that a Kegerator is a mini fridge specially equipped for a keg of beer, please lower your space rifle and step back through the Stargate.  You're in the wrong fucking dimension. 

No Singing 

I hope you don't need to be told this.  The lack of singing is the one absolute.  Any other criteria -- even a few of them -- could be missing from your bathroom and you could still argue that your bathroom is manly.  You can even exhibit emotion in your bathroom.  You can shadowbox.  You can cry (only if you cry blood).  But if you sing one note, you'll have slid onto a slippery slope populated by nothing but smaller dogs, bigger kitchens and shaved body hair.  You'll be a lady.  But you're not a lady, and when you walk through the blast driers and out your bathroom door, you'll rearm your lasers, take a deep breath, and give thanks that you had the foresight to Man Up Your Bathroom.