It's simple! He dies, and he lives, having killed himself for the honor of helping you repopulate the earth. So he walks out of the cage where they fought, a la Mad Max: Beyond Thunderdome, kneels before you asks you to be his bride and then carries you back to your tent which is aboard the Overlord's space ship. He congratulates your future Husband for killing himself in such an exciting and electrifying death match and keeps his word to not destroy earth.