Tink is a young angel-in-training who accidentally grants the unborn Sapphire both a blue boy's heart and a pink girl's heart during a heavenly ceremony, resulting in her dual-gender nature. As punishment for this error, God commands Tink to descend to Earth and retrieve the extra boy's heart from Sapphire. Bound to a mortal form on Earth, Tink becomes vulnerable to physical harm and loses most divine powers, retaining only the ability to blow a trumpet with extreme volume.

He serves as Sapphire's primary supporting character and guardian throughout her journey. Though his mission is to reclaim the boy's heart, Sapphire's persistent refusal compels Tink to stay on Earth as her companion and protector. Tink possesses kindness and good intentions, but his nature is naive, fallible, and occasionally reckless, often charging into situations without fully weighing the consequences.

A key part of Tink's role involves opposing supernatural threats, particularly the devil Satan (or Mephistopheles). Satan harbors a deep fear of angels, and Tink's presence, especially the sound of his trumpet, frequently forces Satan to retreat, disrupting his schemes against Sapphire. Tink also interacts with the natural world, shown cavorting with animals in both the manga and anime.

Tink's character arc concludes in the final battle against antagonist Mr. X. Mortally wounded during the castle's collapse, Tink communicates with God in his dying moments. He offers his own life in exchange for the resurrection of Sapphire’s parents. God accepts this sacrifice, restoring the King and Queen to life as Tink’s spirit ascends to heaven, where he finally earns his wings.

Beyond the core *Princess Knight* story, Tink appears in brief cameos within unrelated Tezuka manga, such as a paperboy in *The Three Who Glimpse the Future* (1958) and a background figure in *Rubbish Poetry* (1969). He does not appear in non-manga adaptations like the 2006 *Princess Knight* stage musical.