Naruto: The Outsider's Resolve - Chapter 1.2 (021):

Athen had always lived a solitary life, as without any family or friends, he struggled to survive in his poor, forgotten hometown. The only escape from this grim reality came in the form of tales of magic told by rare visitors from the distant capital.That was, until one day, Athen discovered that magic wasn't just a dream. It was within him.With his newfound power, Athen completed a desperate heist, stealing a priceless diamond. But his triumph was short-lived when he realized the diamond was a fake.Yet... what seemed like a cruel trick turned out to be a blessing in disguise, for the fake diamond held the key to unlocking Athen’s greatest desire: the chance to truly learn magic.

Vahn was an atypical youth. Due to a rare mutation, his blood had the potential to target and attack ailments within the human body. Touted as a universal cure, people had elevated his status above the norm and given him the classification "Panacea". In the media, he was hailed as a great hero who would usher in a new era or human wellness. However, behind the scenes things weren't so bright. Being a unique individual, Vahn spent his entire youth locked up in a lab with various scientists and research teams using his body and blood to perform endless amounts of experiments. The only solace in his suffering was the various anime and manga made available to him between experiments. He often imagined himself as the protagonist in a world of his own, finally in control of his own destiny. For years he nurtured this desire, until at the age of 14 he died when an organization had tried to kidnap him from the lab...

Ask, under the starry sky there was a beauty, her black hair like eternal night, bright eyes sparkling like stars, her powerful magic made the world tremble, her supreme beauty made all creatures submit, who was this beauty? “That’s right, it’s me, the Witch King, Dorothy!” ‍

The protagonist, Winnie (文尼), confesses his love to his childhood friend—the princess he’s been secretly in love with for years—but is brutally rejected in public. His heart shatters, he’s humiliated and ridiculed, and he collapses unconscious. When he wakes up, he vaguely remembers his past life’s memories and realizes he has transmigrated into the world of an otome game he played before. At first, he’s thrilled, thinking, “Nice! I must have been reincarnated as a villainous side character who disrupts the protagonist’s romance, right?” But then… surprise! He’s not just the villain—he’s the “Saintess”!