Ariel and Herc are technically cousins.
Someone needs to write fic over them going in adventures and bonding pronto.
According to Greek mythology, Ariel’s father, King Triton, is the son of Poseidon, which would make the sea god Ariel’s grandfather. Poseidon’s brother Zeus is the father of Hercules, so Herc and Triton are first cousins. The child of your first cousin is your first cousin once removed, therefore Hercules and Ariel are first cousins once removed.