Finding out as much information on a person without their knowledge using mutual friends or social media.

to go missing without notice

Hanging upside down from something by the strength of your feet and ankles

When someone is performing fellatio on you and you thrust a little too deep, thus damaging their vocal cords and causing them to speak in the characteristically raspy voice of Christian Bale's Batman.

While having sex doggy style, you have to subtly grab the drapes and tie them around your neck to make a mantle (works best with dark or black drapes). When its done you now start to hummm the batman song. From that you continue until your partner notice you are humuming and when (s)he ask what you are doing you start signing out loud, Batman, Batman.

High chance of self cock-block do at your own risk

The ultimate superhero, one that manipulates his enemies' fear and uses stealth and intimidation and intellect to succeed, and does not need butthole Superman powers to survive.

"Until a man is twenty-five, he still thinks, every so often, that under the right circumstances he could be the baddest motherfucker in the world. If I moved to a martial-arts monastery in China and studied real hard for ten years. If my family was wiped out by Columbian drug dealers and I swore myself to revenge. If I got a fatal disease, had one year to live, devoted it to wiping out street crime. If I just dropped out and devoted my life to being bad."
-Neal Stephenson, "Snow Crash"

Batman is a higher state of being particular to fictional worlds. In any given universe, the Batman is that world's biggest bad-ass. This bad-ass is represented numerous ways- strength, toughness, genius, etc. This accompanies strong, authoritarian personalities and immense will.
Though they are not usually the most powerful person in their worlds, they are most certainly the Winners. It is nearly impossible to stop one who has attained Batman. Their will to survive/fight/win is simply too strong.
They're known for taking things "too far". This is quite simply because attaining Batman requires that you're more than a little crazy. Sane people simply would not do the things Batman does. Batman even scares the other good guys.