where one person lurks in the shadows with their true identity known to only a few close friends of the other. This could be because the 'batman' is someone on the side, below the class of whom they are dating ie, when someone is "slumming" or because of fear of judgment by friends. A man or woman can be the batman.
Indication that you are in a Batman relationship include not going out in public together but rather spending time alone together, not meeting friends or family of the person you are seeing, random communication usually via text and not phone, the other person not wanting to join you when you do group activities with your friends, etc.
I think Suzy is in a Batman Relationship, she's having trouble in her marriage, but doesn't seem to be very unhappy.
by Obscure Sarcasm January 24, 2016
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