Damn, I Have to Marry the Strongest Antagonist at the Start? - Chapter 511 - 507-Tsukihime’s Betrayal?

Shion, the ‘Hero of Darkness’. He was said to be the strongest hero ever. He believed one thing, and that was his current party members.

“I’ll defeat the Demon Lord with this party!”

That is what he swore to do, but a tragedy occurs. He was painfully betrayed by the girls that he trusted.

He barely held onto his life, but the incident left a deep scar in his heart.

He gave up on living, and while he was wandering around in a forest, looking for a way to die, a single monster appeared in front of him.

“Will you kill me, please?”

The monster asked Shion, who was still strong, despite losing his powers.

What Shion, who wanted to die as well, did was―

Do you want to know What happens if a cultured man gets a chance to try his hidden Degenerate and taboo thoughts in real life?Yang Chen, Our Main character, gets this chance. Yang Chen grew up with an obsessive love for older women, and all of his wishes came true when Ambulance-kun sent him into the cycle of reincarnation.He reincarnates in Seraphia, a parallel world of Earth. Several hundred years ago, Abyssal trials descended on this world. people were given role-playing missions after being dragged into the underworld.Yang Chen Awakens the Primordial perverted system and System is a fallen angel and an overpowered milf.With her help, He did many perverted things with the roles assigned to him.Yang Chen did taboo sins and conquered milfs as a Village chief, Principal, Masseur, Doctor, Teacher, etc...When He was done with ghost humans, Yang Chen's claws reached out to other races, such as vampires, Succubus, Zombies, foxes, etc...

Year 2056, in a city in the Yuan Jiang Su Jin area. On top of a ruined, shattered six story residential apartment sits a teenager wearing a combat vest, militaristic trousers, and alloyed battle boots. On his back is a hexagonal shield and equipped is a blood-shadow battle knife. He sits there silently on the edge of the roof. At this time, the sparkling sky was shining and there was a refreshing breath within the air that blew towards him. However, there was only silence within the ruined, deserted city, with an occasional howl that makes your heart skip a beat.

- Description from novelupdates

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.