I don't want to have to watch him, sneaking up behind me.

He might just as well sneak up behind somebody and shoot him in the back.

Did you sneak up behind him and tug on it to make sure?

Sneak up behind me while I was studying or something.

He had his head stuck clear down into it and I was able to sneak up behind him.

Another man sneaked up behind him and cut off his head.

And if he were free, I'd never know when he'd be sneaking up behind me.

"How could he sneak up behind you in that small area?"

"It's hard to sneak up behind someone when you're running for your life!"

But as he made his second move, a safety sneaked up behind him.