Human and Non-Human

Dragon spirit and human (albeit a human who is a taoist cultivator with the ML's heart protecting scale and core)

Robot and human

Human and "Doom", an immortal being created by the Gardener (god / mother nature) to balance the scales by directing misfortune on Earth.

Powerful part-human part-spirit frozen in time, neither dead nor alive, and human

Human and a cat who can temporarily take on human form

Angel and human

Ghost and human

Alien and human

"Goblin" and human; Grim reaper and human

Energy-sucking "vampire" and human

Gumiho and human; half-gumiho-half-human and human

Great Sage / monkey deity and human

Human and "human" with a genetic mutation that basically gives him immortality and super powers

Water god and human

Energy-sucking "vampire" and human

Angel and human