Craft Skill de Isekai no Mujintou wo Daikaizou! "......toka Omottara Senjuumin ga Ite, Ore no Kodane wo Neratteiru you desu"

Hayato is a college student who loves crafting games. One day, he's pulled into the game world and awakens to his "crafting skills," which allow him to store materials and build houses. He was planning to live a laid-back, slow life, but that all changes when he meets Leena, an elf girl. He learns that there are no men on the island they're on and that they're desperate for sperm. One after another, girls from different races come after Hayato, all vying for his sperm!! A harem romantic comedy about sperm is about to begin!!

(Source: Yanmanga, translated)