Its when you have sex with suicide bombers before they go off into a crowd of people and blow themselves up. Very popular in Iraq and countries around the middle east. They tend to keep the explosive strapped on to make it more erotic.
The Taliban have said that this is a very effective motivation technique passed down through generation to generation.
Quote from Bin Laden: "I went suicide banging last night, I bleedin lashed yer one out of it. She took it in the back door and everything - the slut. Mad dirty yoke"
When some member of the Taliban has sex with female suicide bombers before they blow themselves up. Its called Suicide banging.