Baka to Test to Shoukanjuu‎ - Volume 11, The Ninth Question

A man was transported to Ancient China and eventually became a servant of a declining household without a male heir. He utilized his wits and modern knowledge to help the household and eventually become trapped in the sea of political turmoils of the period.

- Description from Novelupdates

Seven years ago, she freely and easily abandoned ￥100 and ran away, carrying her unborn son with her. Seven years later, she returned with the lady killer’s genius son, never expecting that her darling son would sell her out to MBS International. Unexpectedly, her immediate superior was the Mr. ￥100 from seven years ago!

One of the rarest type of magician exist in the world. Who would able to underestimate summoning and ordering a mighty pheonix, or summoning an invincible dragon? Of course, none.

To master the path of summoning, only those born with an innate talent and strive to learn the path of summoning magic might be capable of achieving and master the powerful magic.

But not for Lyan Arcanium Evocatore. After succeeding defeating his lifetime quest of saving the human world by offering his life, the great incubus's wish of living freely got granted and he wakes up at a parallel world with 8 powerful spirits contracted with him and a summoning grimoire.

[The gods have granted you the Grimoire of Summoning: Creatures of Love]

[You're capable of obtaining the summonable monsters by having affectionate intercourse with your romantic interests]

[The Grimoire is chosen in consideration of the host's former occupation as an incubus]

“Intercourse!?”

But not only the grimoire, The other problem is...

-You are?

-Whoa... What with this weakling?

-It seems that you're my master, nice to meet you

-So you're the forementioned servant, huh!?

-B-Big bro! Y-You're the summoner!

-........

-Boy, you look delicious

-Um... Where exactly are we?

“How should I know!? And why the hell should I sleep with women in order to get my summonable monsters!?!?”

Follow the summoner Lyan as he collect monsters, get dragged into different kinds of war, became the greatest feudal lord, battling the goblin king, facing the dragon tribe, and opposing the evil god followers!

One of the King of Kings Series