I Was Banished from Heaven, Now I'm the Demon King's Stepdad?! - Chapter 26 – “The Girl Who Shouldn’t Exist

Crossing to One Piece world, he became Roger’s younger brother.

Unexpectedly, Gol-D-Roger who was in his fifties had a teenage brother. But he was so weak.

Fortunately, at the age of sixteen, he actually found himself with a possession soul system.

He had attached to the master IP man, also to the White Phoenix and to Ge Nie with his strong ability of the Hundred Step Flying Sword.

If you think that he can only Purchase these? Then you’re wrong!

Pain, Itachi, Ichigo Kurosaki, as long as there is money, any soul can be Purchased.

- Description from Novelupdates

Every drop of this family bloodline is stained with sin. They are the embodiment of contradiction; calm yet maniacal, with great memories yet often forgetful. They pledge themselves to their dreams yet often compromise, are angels that are also devils… It’s why I hate them. And also love them.

The only hope of his family, a youth with the blood of elves and devils walks on a battleground of annihilation and rebirth. He wills his way through boiling lava and icy depths, killing on this field of despair to strike down the lofty figure in his sight. One day he’ll grasp his blade tightly and survey his surroundings, only to find no more enemies to kill.

“Hero, where are you going?”“To eat.”“Hero, where are you going?”“To the bathroom.”“Hero…!”“…”The woman who followed me everywhere… Ended up following me all the way to Earth.———A former hero who returned to Earth, now unemployed and just lazing around at home.Then, the saintess who came with him made a suggestion—“How about streaming?”“Hmm… This might actually be a good idea.”And so, the Hero & Saintess Healing Stream begins!

There are a total of seven sins, and a revelation is made to a young man named Alex that he is destined to become a demon lord, more especially a demon lord of sin called LUST.

It's not like he can change that and because he always knew something about himself was different—not in a physical sense, well, maybe a little—and not in a mental sense—but rather because he is thrown into a demonic war that compels him to accept his new reality.

He was only aware of a difference in himself. Relating to him and the ladies who are drawn to him... Well, it was more or less like he was a magnet in front of all the girls, and all the girls were drawn to him like a metal.