I was inspired by imagining the Moon as a celestial being of small size, kind of literally thinking in the word "Moonchild", but I didn't want it to look too childlish either, so I thought about adding to it some royal elements like a crown and an abstract collar to represent the divinity of it as a god or a superior existence.
According to Persona 3, which uses the tarot topic to build the story:
"The Moon Arcana is associated with creativity, inspiration, dreams, madness, illusions, fear, fantasy, the subconscious, and trickery. In tarot readings, it can also represent being attuned subconsciously to the world around, gaining the ability to sense things without being told about them or without anyone else knowing (which means that some identify this Arcana with psychic energy)."