He could break the pattern by killing her. Then, as he had planned originally, there would be no childbirth, and no mankind.
He lifted the pistol. The look on his face must have given him away. Probably, she thought it was a club. He was pain-wracked and very much weakened by his disease now. She took the pistol away from him easily, and shrugged, and cried a little, and went away.
He ran after her.
"Wait!" he screamed. "Wait, you don't understand! You've got to die. You've got to—"
He fell. His legs drummed feebly. She was gone. The pistol was gone. Humanity would live—the life of torment and pain and disease that it had always known.
And he would die, alone, wracked by the ailment he had introduced into the human line.
He lay there.
It took him a long time to die.