Queen's Hole

Genius scientist Kanna Heinlein suddenly appears before the self proclaimed sex god of Japan Takayama Yamato and proclaims that she needs to harvest Yamato's sexual energy to save the world! However, while doing so she accidentally teleports them to ancient Egypt. To return to the original world, he must have sex with some of history's most powerful and beautiful women.

(Source: Jitsugyo no Nihon Sha, translated)