Basically, I sent pics of the TWSTD dudes to my best friend and I let her give them nicknames.

Riddle: Kingman

Ace: Punk

Deuce: Nerd

Trey: Smug bastard

Cater: Punkier Punk

Leona: Furry

Ruggie: Smaller furry

Jack: Bastard man/wolf bastard

Azul: The guy who calls you dahling

Jade: Suspicious

Floyd: Also suspicious (Suspicious 2: Electric Boogaloo)

Kalim: FIRE

Jamil: The Backstabber

Vil: Ara Ara~

Rook: Miniature Ara Ara

Epel: Moe

Idia: OH LORD GET THE WATER

Ortho: OH LORD MUTHAFUCKIN BOOTLEG FIREWORKS (her words not mine)

Malleus: Evil

Lilia: Frilly

Silver: Cereal

Sebek: Forehead

That's basically it.