I'm Just a Merchant Traveling Through the Heavens

Fang Xiang's only wish is to live a quiet life as the owner of a convenience store. But then he comes across a shop that can transmigrate across the Myriad Worlds, and suddenly he has a few more wishes:

"I'll open my shops across the Myriad Worlds!"

"I'll sell technology-based weapons to magic-based worlds!"

"I'll make primitive people call me Dad!"

"And I'll... bring world peace!"

And so, one product becomes a runaway hit in the world of Demon Slayer: a UV flashlight!