How Is Reincarnation Used As A Plot Device In The Reincarnated Assassin Is A Genius Swordsman?

A witch who has lived for thousands of years has grown bored with her own life and decided to leave it. Since she is an immortal, her soul cannot leave the world. However, what she can do is transfer her soul to another body. By a stroke of luck, she happens to enter the body of a princess. She was considered a miracle because when the Empress gave birth to her, the princess instantly died, along with the Empress. What the witch didn't know was that she has entered such a predicament. She has to endure the love of the cruel Emperor and possessiveness of the crazy twin princes! What will her life be at the hands of such a loving family? In addition, it seems that this body contains mana that was lost in the royal family centuries ago!

Al, was thrown into another world for no apparent reason. A new world filled with magical things. However, this wasn't the first time he had been reincarnated. He thought he was just an ordinary youth, but it turned out that his identity was so extraordinary in his first reincarnation. There were his harems still waiting for his arrival. Will he meet them soon and what will happen?

Sheeran, a 16-year-old boy, lived until he was killed for a stupid reason. ( stupid reason & more in the prologue:v ) But it seems that fate had stored different things for him as after death, His soul transmigrated to another world inside a dead body of a boy with the same name and same facial features as him. He also found out that a mysterious black whirlpool seemed to be inside him and connected to his soul. After the short unfortunate first life, he starts living his second life with more suffering that he chooses himself to get stronger but with that also comes happiness he had never experienced. A smooth sailing second life of Sheeran starts with something mystical inside his body and other benefits of it that could make him stronger with some suffering. However...he didn't know that due to his soul ( That was supposed to return to the source of the universe after death but instead, it transmigrated by someone for some purpose and that caused an adverse effect like increasing misfortune on his soul ) The benefits he receives ultimately becomes the source of his second doom that is even worse than death. But...that's when the future revoked overlord is born.

At my 20th birthday banquet, I am to sign and receive the ten-billion-dollar inheritance left to me by my mother. My half-sister, Samantha Hatfield, and Howard Daley, her husband, who is also a secretary, eagerly urge me to sign the document. In my previous life, they trick me into signing the very same agreement, and the inheritance somehow becomes theirs. When I try to fight back, no one listens to me. Together, they have me confined to a sanatorium, where I spend the rest of my life drugged, imprisoned, and forgotten. But this time, their scheme is going to fail—I have returned with memories of what happens from the past life. Under their confident, expectant gazes, I pick up the pen. However, I do not pick it up to sign. I raise my hand and slash the pen's tip across Howard's face. As he lets out a terrified scream, I tear the agreement into pieces in front of all the guests and hurl the paper scraps at them. I say coldly, "My mother left all this to me. What makes you two heartless parasites think you're worthy of laying even one finger on it?"

The first thing I do after being reborn is secretly keeping six stunning male models behind my wealthy husband’s back. I seduce them and sleep with them for 999 days to get myself pregnant. I do all this because in my past life, my husband found out that he had asthenozoospermia and married me because I am known for being fertile. He wants to carry on the family line so that he will have a successor to inherit the family fortune. I try everything I can to get pregnant, but nothing works. Conversely, my infertile best friend gives birth to twins and triplets within two years after marrying a 70-year-old man. When my wealthy husband hears that my best friend is blessed with children, he is immediately captivated. They get together behind my back and even arrange for someone to run me over with a car when I find out the truth. After my death, I discover that my best friend has bound herself to the child switch system. Any child I am impregnated with is transferred into her womb. My best friend's infertility is transferred to me in return. When I open my eyes again, I find myself back on the day when my husband married me and brought me home. I smile happily when I think about all the things that took place in my past life. My best friend wants lots of children, doesn't she? If so, I will make her experience the joy of having 18 babies in one pregnancy!

A 25 years old boy named John is suddenly shot by his friend, which results in his death, but is reincarnated again as the new Demon King. Unfortunately, he agains dies in a battle. This time also he is reincarnated but as a human. Follow Vis' adventure as he gets revenge, becomes a demon and makes his own harem.