A lot of restaurants like to be creative with their signage for bathroom doors. I get that. It's kind of nice for a restaurant or pub or other bathroom-having establishment to put their own spin on the traditional "Men" and "Women" titles. You know, make it their own.
There are some great ways to do this. They could post a photo of a famous and glamorous lady and a debonair gentleman. They can do some artistic rendition of the usual silhouette forms of people with or without dresses. They can use "clever" terms like "Dudes" and "Dudettes" or employ any other option out of the myriad of bathroom door signage options.
I have but one request: don't use words or images that will force your patrons to stop in front of the two doors and consider for more than a second which one they're supposed to choose.
It's awkward to stand in front of any door, unsure if you're supposed to use it while other people bustle by, judging you for your low reading comprehension. It's more awkward when it's a bathroom door and you don't realize you've been staring at the wrong door until someone from the opposite gender comes through it and you have a horribly uncomfortable moment of eye contact just as they've exited the bathroom and you both know what they were doing in there. Plus it makes you look creepy.
Just a little tip from your neighbourhood bathroom-goer.