Non-humans and their blood color (not an exhaustive list):
Xylia and Kayson both have ichor instead of blood, being Greek creatures on both sides of their parents.
Phoenix takes more after his mom, his blood looks vaguely like tree sap, his bruises tend to look more yellow/brown, like humans who’ve healed a bit.
Fiacre’s is a murky brown, like muddied water.
Jinx and Yuki both have red blood, like a human. Elves aren’t too far off from that and Yuki took more after his mom on that front.
............Harmony just doesn’t bleed so that sure is Something but they’ve also said they don’t have any bones so idk man I shouldn’t be surprised.
Ivar’s is gold. His skin also faintly glows gold to non-human eyes.
Roxy’s is a light purple, kinda violet.
Caspara’s is a darker purple.
Aries has a shimmery silver.
Ultan’s is grass green.
Kiyoshi bleeds a blue-grey color, like the sea during a storm.
Naoise’s is a shimmering black, like the night sky.