Adam to Eve ni Narenai Bokura

A handsome younger man with a sharp sense of humor, and an unlucky virgin boy burdened with crippling self-doubt. Saddled with his deceased parents' debts, Warabi Souta leaves Earth as a planetary emigrant, hoping to start his life over on his own terms. But when his spaceship crashes, he awakens alone on an unknown planet. Just as despair and isolation threaten to consume him, a mysterious creature attacks—and the one who comes to his rescue is Ichiroku, a fellow passenger from the very same ship.