Transmigrated Become Sukuna, but the host is Yukinoshita Yukino? - Chapter 31 - : Increase the Intensity.

Amakawa Haruto died before he’d the chance to reunite with his childhood friend who disappeared five years ago. Rio, a young boy living in the slums seeks revenge for his mother who was murdered in cold blood in front of him when he was only five years of age.

There exists the earth many knows of and there exists an alternate world. Two people, each with their own backgrounds and values. For odd reasons, the memories and personality of Haruto, one who should have died resurrects in Rio’s body. As the two are confused over their memories and personality fusing together, Rio (Haruto) decides to live in this new world.

Along with Haruto’s memories, Rio awakens an unknown but special power. If he’s to use it, it looks as if he can live a better life, but before that, Rio encountered a kidnapping which results in involving the two princesses of the Bertam Kingdom.

After saving the princesses, Rio is given a scholarship to attend the Royal Academy, a school for the rich and powerful. His background being a poor orphan who once lived in the slums, the school full of nobles was rather a detestable place to stay at.

On modern-day Earth, An Lin seems to have been abandoned by God.
When his father suddenly disappears, An Lin is left with his father’s immense debt, putting his life at risk.
After being forced to a rooftop by his pursuing creditors, An Lin is unexpectedly swept off his feet and brought to the ground safely.

After learning that he was saved by an Immortal, An Lin is gifted, seemingly out of pure generosity, the ‘God Of War System,’ and a pass to a new realm.
Follow An Lin as he experiences a whole new world of legends, meets many new friends, acquires legendary weapons and tools, and starts on his path of becoming a powerful cultivator. There is never a dull time in An Lin’s new life with his ‘great’ new system!

- Description from Novelupdates

Teresa is a timid human whose life has been a series of unfortunate events—until she meets Lucian Blackwood, a very rich and handsome man who awakens a deep, unexplainable connection within her. But Lucian, an alpha werewolf with a haunting past, is repelled by Teresa’s perceived weakness, blaming weakness for the tragedy that shaped his life. Unable to accept her as his mate, he rejects and humiliates her, leaving Teresa shattered.Just as she’s picking up the pieces, Adrian Daegon, an ancient vampire with his own dark allure, steps into her life, determined to win her heart. Now, Lucian is torn with regret, desperate to reclaim the woman he cast aside. But to do so, he must face a powerful vampire and confront his own fears—while somehow convincing Teresa to forgive his betrayal and reignite their lost bond. Can love and redemption overcome the scars of rejection, or has Lucian's cruel mistake cost him his mate forever?Torn between two powerful forces, Teresa must decide where her true destiny lies—in the fierce grip of the wolf who scorned her or the dark embrace of the vampire who vows to adore her.