MTL - Pokémon Modifier - Chapter 575 Sticky dragons

Kael was a “rat”—a lowly stable boy in a frozen, brutal medieval world where Knights ruled with iron and Barbarians crushed skulls with bone clubs. His life was worth less than the manure he shoveled. That changed the night he butchered a Knight with a rusty dagger to pay a debt of blood.Chosen by the God of Slaughter, Kael awakens the Aether System. His cheat? The ability to project his soul into other worlds, live countless lives, and bring their powers back to reality—if he survives.But power is not free. It is bought with pain, time, and sanity.World 1: The Wild West. He spends a lifetime as “El Lobo,” a legendary gunslinger. He returns with the muscle memory of a master marksman and a 12-gauge shotgun. World 2: The Martial Arts Realm. He trains for decades as a Wuxia disciple. He returns with internal energy that can shatter steel.Now, as the Kingdom faces war and monsters surge from the dark, the nobles sneer at the servant boy holding a strange metal tube. They chant spells. They draw enchanted swords. Kael takes a slow breath. He racks the slide. Click-clack. “Parry this.”

MC (female protagonist) dies in a plane crash and wakes up in the body of a beautiful but corrupt and lascivious prime minister in ancient times, Zhang Qinglian. As circumstances decree, he (she) cannot reveal that the original owner’s soul is gone else calamity might occur. So he (she) decides to walk a righteous path, determined to help the lovely but simple little emperor rule the country. Not backing down after facing torture, not losing courage, destroying rebellions and facing off with scheming princes.

- Description from Novelupdates

A polite and lethargic boy was reincarnated in another world as a vampire bishoujo.