English name: 3Ping Lovers! Ippu Nisai no Sekai e Youkoso The Animation
Original name: 3PingLovers!☆一夫二妻の世界へようこそ♪ THE ANIMATION
A high school senior gets transported to an alternate reality where he has to save the world using his semen. Female guardians of this realm need nourishment to vanquish the evil that lurks beneath. And there's only one man who can provide them with what they need.