He tightened his own hands into fists, for a moment.

My hands tightened into fists, the thought not sitting well with me.

As he had expected, her lips tightened into a thin line.

Whatever she'd been about to say died on lips that tightened into a straight line.

He didn't move back, but his hands tightened into fists.

He raised his right hand and tightened it into a fist.

She drew away from me and tightened the hand into a fist.

Meanwhile, his right hand had tightened into a fist again.

He then tightened his hands into fists, opened them flat again.

Her fingers in his hair tightened into fists from the pain.