Lotte no Omocha!

Lotte no Omocha! (ロッテのおもちゃ!, Rotte no Omocha!?, "Lotte's Toy!") is a Japanese manga series written and illustrated by Yui Haga about Naoya, a man brought to a magical world as a candidate for the Princess Astarotte's harem. Lotte no Omocha! began its serialization run in the July 2007 issue of Dengeki Maoh and later republished in collected volumes by ASCII Media Works. In 2011, the manga series was adapted into an anime television series under the title of Astarotte no Omocha! (アスタロッテのおもちゃ!?, "Astarotte's Toy!"), produced by Diomedea under the direction of Fumitoshi Oizaki which aired between April and June 2011.

Story
In the medieval fantasy world of Álfheimr, succubus princess Astarotte Ygvar, the first princess of the kingdom of Ygvarland (ユグヴァルランド Yuguvarurando), has just reached the age of 10. For the coming years of a young succubus' life, it is necessary for them to have a male harem. In order to maintain their body and preserve their beautiful appearance, they must consume a substance only found on males. This substance is a liquid called Sauzfryma, better known as semen. The princess, however, bears a great dislike against men, and only agrees to create a harem if a human male is to join, as human males are said to be impossible to find. However, her followers are somehow able to find a human male named Naoya Tohara who, along with his daughter Asuha, is brought to the demon world to be part of Astarotte's harem.