DxD: Matsuda? - Chapter 1: Really God, Matsuda?

I was a failed experiment

[Beast Mastery][Summoning][Pets][Evolution][Development]Demon, Savage, Nether, Damnation, Mechanism, Soldier, Medicine, Abnormal, Witch, Immortal, Ferocious...This world is a world of monsters, filled with countless diverse “Fond Spirits”.But in this world, humans also wield the power of “occupation classes”. Once awakened, they can have Contract Imprints, allowing them to form contracts with the monsters, creating entirely new bonds.[For Instance]♦F-level Occupation Class “Manicurist”- helps the Fond Spirits trim their claws, making them beautiful, or sharper.♦E-level Occupation Class “Hunter”- marks and chases, closely collaborating with the Fond Spirits, the most classic hunting occupation class.♦C-level Occupation Class “Puppeteer”- manipulates Fond Spirits at crucial moments, making their strikes more precise and powerful.♦B-level Occupation Class “Midwife”- assists pregnant Fond Spirits with health checkups, giving random blessing effects to the newborns.♦B-level Occupation Class “Mechanic”- under the right conditions, modifies the Fond Spirits, turning them into semi-mechanical beings.♦A-level Occupation Class “Dragon Knight”- rides dragon-type Fond Spirits into battle. Man and dragon unite, becoming invincible.♦S-level Occupation Class “Arch Warlock”- intensifies the elemental properties of Contracted Fond Spirits and seals their skills in advance to execute forbidden spells for the second time....♦C-level Occupation Class “Fitness Trainer”...♦D-level Occupation Class “Flame Thief”...♦A-level Occupation Class “Mysterious Merchant”...♦B-level Occupation Class “Gourmet”...♦Special Occupation Class “Brave”......(I already have a completed work of 3 million characters titled “Master of Pets”. “The Rising of the Fond Spirits” is my second work, a Beast Mastery tale with entirely original settings, you're welcome to try it out!)

In a future timeline, the earth was visited by a species known as the Slarkovs.
Having lost their home planet and in search of a new one, earth was the next habitable planet for them.

Humans and Slarkovs made a deal with each other in return for the Slarkovs living on earth.
The Slarkovs traded their technology and knowledge for a new home.
They were similar to humans except for some of them who had slight differences so fitting into the society wasn't a problem.
Over the years Slarkovs and humans began to mate with one another and reproduce offsprings.
This in turn created a new species known as the mixed-blood.
Centuries later mixedbloods could tap into their bloodline and perform unimaginable feats.

Gustav born into an age where bloodline determines everything, struggles to fit with a useless bloodline.
His bloodline only grants him the ability to change his hair color, destroying his hopes and dreams for a great future.
His fate is turned around when an unexpected situation leads to him finding a system that grants him the power to unlock and upgrade bloodlines by completing quests but he's baffled by two quests with a five-year deadline. Success will grant him unimaginable rewards...
But only one thing awaits him if he fails... Death!

Follow Gustav on his interesting journey filled with unprecedented adventures, danger and death, maybe?

Why did an incubus become the most coveted species among the most powerful and sought-after empresses, even by primordial goddesses?!

There is a famous legend on the ALZANIA planet. Who says that once every hundred thousand years, an incubus will be born, through a mystical ritual. He will possess mysterious powers that could allow any empress mage to reach divinity, any goddess to achieve supremacy!!....... But would the possessor of such power have the blessing of a peaceful life?!------

Follow the daily life of Alvine, who had just opened his eyes, who suddenly found himself in the body of a boy celebrating his 18th birthday.

[ Ding!! ....]

[The host has reached the age required for activation of the succubus gene ]

[The transformation process into an incubus will begin in 5 seconds... 5....4...3..2..1...]