I'm Too Sober For This (Crossover Fanfic)

Author:Masked Spider

Summary: Shirou Emiya has had an interesting time adjusting to the world of his new king, Serafall, but not a terrible time. That is until a spell gone awry brings a different, and far more irritable, Issei Hyoudou into the fray. Will they get along or is a giant mess in store for the both of them? Either way it's gonna be quite a time for the world caught in the middle! GAIWP x ADLH

Source:Fanfiction.net

Thoughts: this is a collaboration between two recommendations whose authors chose to work together. This time we have a crossover between the Highschool DxD fics 'Go Away I'm Watching Porn' and 'A Demon Lord's Hero'. One of the store I would recommend it's hilarious seeing two different types of essays interact but doesn't focus on it. You have a mentally unstable version issei meeting Shirou Emiya in different Dxd world. It gets even meta with GAIWP Issei literally telling shirou his a fictional work.