Eastern Evil Cultivators Travel Across the Western World

Give Voldemort a Little Bit of the Shock of the Eastern Demonic Cult

I'm looking for a book about Voldemort. A cultivator from the Eastern Demonic Cult came to HP and discovered Voldemort. I originally wanted to have a conversation, but found that Voldemort was a little too childish compared to those in the cultivating world. Then I told him about the Eastern cultivating world, and then Voldemort fell in love with the protagonist.