His gaze slides away, past her again. It's a hard decision. He did promise... but he also knows what happened the last time he was supposed to kill Steve Rogers. And he didn't even know why, last time. This time, he knows. "I'll think about it."

Then he holds out his hand in her direction, vaguely, like he wants hers in it. Not alone. He's at least holding onto that. "I. Hope it never happens, too."