Lapis is a female Russian Blue cat Jewelpet with slender, bluish-grey fur and cyan inner ears. Her eyes are made of lapis lazuli gemstones, and she typically wears a golden beaded bracelet on her front left paw and a golden collar with a tear-shaped jewel. She is classified as a Magical Blue Class Jewelpet and represents the concepts of Strong Fortune and the Destruction of Evil.

In terms of personality, Lapis is one of the more mature and snarkier Jewelpets in the anime. According to official material, she has a fondness for horoscopes and is known to look up at the stars of the night sky in search of good fortune. Despite her sometimes sharp demeanor, she displays genuine concern for those she cares about. In the first series, she is initially a member of the Jewel Eight group. She becomes corrupted by the antagonist Dian and turned into a Dark Jewelpet. During this period, she shows concern for King after he is kidnapped following a defeat in the Jewel Game. Later, she is freed from the dark magic together with King, but the two end up imprisoned.

Over the course of the franchise, Lapis undergoes notable development. In later series, such as Jewelpet Kira Deco and Jewelpet Happiness, she runs her own bar, which is known for having a more mature and sophisticated atmosphere compared to other establishments. Characters like Coal, Io, and Kaiser frequent her bar, indicating her integration into the broader social world of the Jewelpets. Her key relationships include King, with whom she shares a bond that survives her corruption, and the other Jewelpets she encounters throughout her journey. Her magical abilities are tied to her jewel eyes and her representation of strong fortune and the destruction of evil, allowing her human partner to bring luck or vanquish malevolent forces.