Eclipse (Male reader x Demon slayer AU)

"They say blue moons are rare. I guess I am rare too then." -Y/n

Welcome to demon slayer but only certain people can learn breathings. Only girls can learn breathing, with the exception of boys with Marechi blood. Sadly those boys die before they can learn any breathings. The other exception are boys who make breathings but they have to see the breathing they branch off of or are related to people who use breathings.

Say hello to Y/n Tsugikuni who is the decendant of Yorrichi but he doesn't know about sun breathing until...