Last Harem [Final] By Kokudo Studio

Set the girls up on the factory line and get impregnating! Faster! More efficient! Industrial engineering sure is something, huh? Dig up a strange, tentacled creature from the depths of the ocean and put the girls to work as seedbeds! Become a tentacle beast yourself and impregnate multiple girls at once!

A gate to another world created in order to meet new species. Get yourself some big strong orc babies, and meet elven and dwarven maidens! A girl living in this ruined, forsaken world. After finding out that you have awakened, she decides she wants to join your harem. She was looking forward to meeting a man, but instead, was taken to the impregnation factory.

A being from another world. Her people have been oppressed by the orcs for many years, but your army saves them. As thanks, she offers her hand in marriage. A species that lives underground in another world. Your relationship begins after you save her.