Very Pure and Ambiguous: The Prequel - VPAATP - V4C51 – Someone Wants To Investigate Me

There are times when all it takes is the right voice to help you realize the greatness within to conquer the painful evil without. Uzumaki Naruto's voice of promise turns out to be his... from the future.

Juvenile Luo Yang, because of the body being blocked by evil dragons, and with the blood of God, has embarked on a road to heaven! Rise from the humble, turn the mountains and seas, step into the world, and press the heavens!

- Description from 69shu translation

She was born into a powerful family of the nobility, a blue-blooded aristocrat as capable as any man. He rose from humble origins up the military ranks, an iron-blooded knight with high ambitions. A transaction for power severed her from her childhood sweetheart. A tardy encounter was the beginning of his and her vow to meet life and death under heaven, standing shoulder to shoulder.

Political intrigue, dynastic succession struggles. He trampled through it all in the toil of becoming emperor.

Old enmities became new disputes, concerning life and death of entire families. She entered once more into the palace, changing the entire political climate of their world.

Meeting once again, they had become strangers. The peach blossom were all fallen, no more than a golden age grown cold.

- Description from Novelupdates

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