MerMay 2020: The Fathom Thieves

This gives a whole new meaning to the word "Mersona".
Looks like the Phantom Thieves of Heart have stumbled upon an undersea palace in the metaverse somewhere and, rather than changing into their usual heist attire, have instead transformed into merpeople to better traverse the environment—pretty cool, huh? (I can imagine Ryuji's first words upon discovering his tail would be "For real?!")
Anyone who knew me in the fall of 2018 knows that Persona 5 absolutely consumed my life. Not only was it one of the best JRPG's I've ever played, but its style and panache inspired me to take my own art, writing, and aesthetics even more seriously (because aesthetics are all that really matter in life... right?). To honor my love for this game (and series in general), as well as to continue along with the MerMay festivities, I thought I'd draw a few of my favorite P5 characters as mers! I might have to draw the rest of the Phantom Thieves (and their confidants) as merpeople in the future... in the meantime, here are my headcanons for what sort of mers they might be:
Yusuke: some sort of porpoise or whale... perfect for our Blizzard Boy
Makoto: a lobster or crab (complete with claws for punching)
Haru: maybe some sort of nudibranch? I haven't settled.
Futaba: definitely a Lovecraftian-style cephalopod, come on
Joker & Akechi: idk man, maybe their tails could change with their different Personas?