MTL - Bourne: Command and Conquer - Chapter 28 , Sima Road

A world where God will grant abilities called Skills to those who come of age. The protagonist, bestowed with two skills, uses them and rises to an existence called a hero.

Until he became the lowest-ranked master, his lonely and luckless life never changed.

Suddenly one day, a descendant injected him with a nanomachine, and the machine started ‘speaking’ to him.

“What? What are you talking about?”

This was beyond the boy’s knowledge, he turned pale.

The Nanomachine linked to his cerebrum realized the User was not understanding a single word it said.

“Who are you, and why are you doing this to me?”

“Nano Mashin?”

The boy’s face hardened.

Mashin was the deity the Mashin Religion worshipped, along with the Sacred Fire.

The religions’ Master communicated with Mashin.

“Um, are you really Mashin?”

The boy knelt down and asked with a trembling voice. At this, the Nanomachine attached to his cerebrum realized it had been misunderstood.

He was very happy to be reborn, but why was he sixteen again, he can’t bear to look back at that time.

Why does he return to being sixteen years old, yet still meet Doomsday?

It’s alright to encounter the end of the world, so why did he have to fall in love with someone?

Even if he falls in love with another person, why did it have to be a man?

Falling in love with a man is also alright, so why did it need to be a secret one-sided love?

Even a secret and unrequited love is alright, so why is that man his….

- 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.