The corner of his mouth twitched, telling her he was trying hard not to smile.

The right corner of her mouth twitched at the thought.

One corner of his mouth twitched, which told me a thing or two.

And the corners of his mouth twitched for a second.

A corner of his mouth twitched and he went back to sleep.

A corner of her mouth twitched as if she were trying to smile.

She turned to him, the corner of her mouth twitching in a smile.

The corner of his mouth twitched, but it wasn't a smile.

The corner of his mouth twitched again, but not with humor.

She and a corner of his mouth twitched at the memory.