Zero no Tsukaima - Volume 5 Chapter 2

One night a mysterious and unexplained phenomenon occurs in the nine provinces. Five years later Chu Feng, a regular outer disciple of the Azure Dragon school, awakens one of the mysterious nine lightning beasts. And discovers an egg sealed inside him.

From there we follow Chu Feng as he crosses the continent, beating up strongest senior brothers, raiding tombs, destroying sects and of course as he conquers beauties.

"Be my son's mother."

Descent of the Phoenix – 13 Years Old Princess Consort

The strongest female assassin from a special assassination force met her death one day on a mission. To her surprise, she woke up in the body of a 13 year old girl, Mu Rong Liu Yue. Through Liu Yue’s past memories, she found out that she was bullied due to the huge birthmark on her face, even though she came from a renowned family. Liu Yue was beaten to death by her own cousin, and that’s how she managed to enter Liu Yue’s battered body. The assassin then decided to live her life as Liu Yue and swore to avenge her death.

- Description from Novelupdates

15 years ago the world discovered magic as well as mythical beings (basically beings from various legends) in another dimension. Humankind learned to summon these dangerous mythical beings and use their power to great effect. Seven countries formed contracts with these “mythical beings” and gained their allegiance as a result. The mythical beings will choose their summoners on their 14th birthday and give them a stigma. Schools have been set up to train summoners and magical swordsman (basically bodyguards that give the summoners time to cast their spell) as a result.

15 years later after the finding of magic Kazuki Hayashizaki is chosen as a summoner and given a stigma to indicate that. This is surprising since males aren’t chosen as summoners due to their low amount of mana compared to females. As the first male to be a summoner Kazuki is under a lot of scrutiny by almost everyone.

To complicate matters his sister (who’s a magical swordsman) is against him going into summoner school to train there as a summoner. Because summoners and magical swordsman have a cat mouse thing going on where summoners look down on magical swordsman as inferior so his sister naturally is against him going there. She’ll stop him even if it means going to war.

Kazuki however is determined to thrive in summoner school and has already determined to give it his all. Even if he’s the lowest ranked student (ranked E) and his fellow students intend to demean him he’ll prove himself as the strongest summoner.