What does it mean when a girl bumps you with her butt?

[LinkxPeach]

This Sunday, at church the church service was over and I was trying to talk to my friends and a girl behind me push her butt against me. Then, I walk to talk to a female friend of my mine and she walk past me and push her butt next to my hand. But, I managed to talk to her anyway. Are there any reasons why she bump her butt against me?

[Anonymous]

To give you a chubby?

[Charleslvajr]

It means you were standing to close.

[BlackieJ]

She likes you.

[Anonymous]

To fart on u