Is taking a photo on a dslr without a lense on bad?

My brother took my camera and tried it while i wasn't home >.< will it effect it? Its a nikon d5100

Added (1). Thanks.

Should not affect it, other than it is more likely to allow dust to get on the sensor.

You should sit your family down and let them know that a DSLR is not a toy, and if damaged, can cost hundreds of dollars to fix… Well, you know the idea.

Shouldn't take anything…

no lens means that all the inner workings are open to the world…

and you need the lens to focus the image onto the sensor - or you just get nothing…

No.It'll just be unfocused light, but it won't harm the camera at all.

Yes.

It won't ruin it, but when you take a photo, the sensor has an electrostatic charge on it. That charge will attract dust to it. With the lens off, all of the dust in the surrounding area can get pulled into the camera body and onto the sensor. If you see dark spots on your images you will need to clean the sensor.

NO, just pretty stupid.