Written by Ford1114 
, Persona Vein (alternative link here) is a Persona 5 and Code Vein crossover, with elements of Nioh, and Kakegurui.
It is part of the Akane no Mai series.
Taking place four years after the canon storyline, the former Phantom Thieves are having normal adult lives. However, a Revenant (Who is the main customized Code Vein character) named Sion is accidentally transported to the present from his future timeline. Within his existence, this causes the reawakening of the legendary vigilantes, the involvement of Yokai and Guardian Spirits, the Lost monsters from Sion's world, and two young women (Hifumi Togo and Yumeko Jabami) to be involved in one mystery.
This story feels like an OVA with six long chapters akin to Digimon Adventure tri., especially the roles given to the Phantom Thieves and Hifumi. The first three chapters are serve as a promotion to Code Vein before the game's release. Meaning, this is the first Code Vein-related fanfic to date. Originally, the author would have planned the later chapters (Act 4 - Final) to be uploaded after Code Vein's initial release (September 2018), but since the game is pushed back to 2019, he has completed the story and showed surprises.
Spoilers are unmarked.
A sequel entitled Urban Legends is written by Kanius with the author involved in the production.
Also, an upcoming consolidated story remake of both this and Urban Legends is coming in 2020. It will bring new changes/corrections relating to Persona 5 Royal and the completed Code Vein, alongside other things serving as a revise/final draft.
This fanfic provide examples of:
- Adaptational Badass:
- The Phantom Thieves' return in the first chapter showcase their experienced status such as wielding their Ultimate Personas, especially Satanael as Ren's signature Persona.
- Both Hifumi and Yumeko are given Guardian Spirits in allowing both to fight in the same level as the Thieves.
- In the penultimate chapter, Hifumi becomes a goddess that she granted the Phantom Thieves and Akechi in fusing their Personas to gain Persona's Ascendancy.
- Bloodier and Gorier: Since there are no Shadows the heroes fight, most of the monster deaths are done by being torn apart in full bloody detail.
- Ship Tease:
- Throughout the story, there are moments that Hifumi and Sion are going to pair up. They finally did in Ch. 5 engaging in sexual intercourse. Sadly, Sion fades out of existence after the final battle, but there is hope when Hifumi meets Skyler.
- Ch. 3 took a glimpse to see a potential pairing of Makoto and Haru when they accidentally touch each other's hands in an onsen. They become an official couple in Ch. 5.
- Shout-Out:
- Some of Joker's fighting styles are taken cue of Mad Dog of Shimano.
- During a conversation in Ch. 3, the group mentioned a fanfic that crossover the Phantom Thieves meeting My Hero Academia. This referenced Thieves Can Be Heroes!.
