The protagonist of the novel, Xingyin is the daughter of the Moon Goddess Chang’e and the famous mortal archer Houyi, born immortal because of the Elixir of Immortality. She grows up sheltered and hidden on the moon, her existence a secret from Celestial royalty. She is curious, determined, and adventurous, but often acts without thinking or understanding the consequences until it is too late. She has a strong sense of Familial Duty and is fiercely loyal to her loved ones. She is determined to free Chang’e and return home after she accidentally ends up in the Celestial Kingdom.

She values pride, honor, and honesty; her candid personality wins the affection of Liwei, the Celestial Prince, and Wenzhi, captain of the Celestial Army and secret prince of the Cloud Wall. When calm, Xingyin can think logically and strategize, but she is often influenced by her strong emotions, which causes her to rush in or act thoughtlessly, complicating her circumstances.

Xingyin is new to romance and explores different forms of Romantic Love. Though her character matures over the course of the novel, she is torn between Liwei and Wenzhi for much of the story, separating from and reuniting with them several times.