It's Actually Not Easy Wanting to be a Supporting Male Lead - Chapter 17 part9

In the eyes of outsiders, Hyuga Yuuto is a genius in the traditional sense of the Hyuga family:

Tough, strong, gentle, and calm, he is a partner worth relying on at all times.

However, no one knows, in countless silent nights.

The young genius of the separation family stroked the caged bird engraved on his head and fell asleep with the sharp needle in his mouth, fearing that in his sleep he would reveal the madness and anger deep in his heart——

“What Uchiha Itachi can do, I, Hinata Yuuto, can’t dare to do?”

- Description from novelbuddy

Born with RH-null blood group, living among the extraordinary vampires, who could perform wonderful feats and possessed magic...Kayden was simply an incapable vampire!

On the halloween night in his school, Kayden explored the biggest perk which came with his incubus blood!

“So, I can charm girls and make them yearn for my touch!? From where should I start now?”

Pairing up with his succubus partner he was determined to find the cause of his mutations. Until unnatural murders occurred from his wrong touches!

Intimacy, blood, life force, he has all the options to stand atop of everyone. Unbeknownst to him that his peculiar blood is desired by all the existing races, as powerful elixir!

Eren Idril died as an old, decrepit, and piss-poor adventurer by the maws of a D-Rank monster. He had a lot of unfulfilled dreams and desires that couldn't see the light of the day after the light in his own eyes died down.

But fortunately for him and unfortunately for the world, that wasn't his end. Eren was somehow dived back in time when he was a mere teen, attending Lionheart Academy for adventurers.

When life gives him a second chance, Eren decides to exploit it to its fullest. Experience his vile deeds as he partakes in them without feeling the slightest bit of hesitation.

I got transmigrated into a game I’ve never seen before.

I thought it was a top-notch RPG and spent 30 years on it.

I retired as a war hero and planned to spend my remaining time leisurely.

But it turns out, it was an academy story?