Covinhas, known as Dimple in some localizations, is a recurring character who begins as an antagonist before evolving into a supportive, though still self-serving, ally. He is a self-proclaimed upper-class evil spirit, easily identified by the distinctive red circles on his cheeks that appear on the faces of any human he possesses. His natural form is typically that of a wispy, floating green cloud of smoke, sometimes forming arms and rarely legs, always bearing a detailed, human-like face with a prominent nose and lips.

His background is largely rooted in his existence as a spirit. His oldest memory is of already being a ghost in a cemetery, and he is uncertain if his own grave is located there. For decades, he existed in this form, at one point leading a gang of spirits until he was nearly exorcised by the immensely powerful spirit Mogami. Covinhas initially harbored grand ambitions of becoming a god worshipped by all of humanity. To this end, he founded a laughter-based cult named LOL, using hexed smile masks to force his followers into perpetual, mindless laughter. His plans were thwarted when he attempted to recruit Shigeo "Mob" Kageyama, who proved immune to the hex and exorcised him. Despite this defeat, Covinhas reformed the very next day and proposed an alliance to Mob, pledging to avoid causing trouble while secretly plotting to eventually possess the young psychic.

In terms of personality, Covinhas is brash, humorous, and often speaks to others using familiar nicknames, such as calling Mob "Shige-chan" until corrected. Beneath his carefree and often comical exterior lies a sharp perceptiveness. He is highly adept at quickly identifying psychological complexes in others, such as Teruki Hanazawa's superiority complex and Ritsu Kageyama's inferiority complex. He also possesses extensive knowledge of spiritual and psychic phenomena. While his initial motives are purely selfish and exploitative, over time his character shows significant development. He transitions from a scheming opportunist focused on godhood to a being capable of genuine concern and loyalty. He frequently advises Mob on social matters, warning him about potential misunderstandings and deceptive situations. During a crisis when the Kageyama home is set on fire, Covinhas showed authentic worry by searching for clues of a struggle and trying to protect Mob from upsetting discoveries. In a critical moment when Mogami separated Mob's soul from his body, Covinhas used his sole chance to possess Mob not for domination, but to safeguard his body, even forgetting his own ambitions to become a god until later reminded.

Covinhas' role in the story is multifaceted. He serves as a comedic sidekick, a source of exposition about the supernatural world, and an occasional moral compass for Mob, offering advice on social and emotional matters. He joins Mob on numerous missions, often collaborating with Arataka Reigen at the Spirits and Such Consultation office. He also develops a key working relationship with Ritsu Kageyama after being allowed into the Kageyama household. His development culminates in the Divine Tree arc, where he acquires godly powers but ultimately expresses admiration for Mob's humility and his philosophy that true strength is hard-earned and not solely dependent on psychic advantage. He praises Mob for perceiving his true feelings during their confrontation. This marks a complete departure from his original goal, as he comes to respect Mob's worldview and prioritizes his bond with the boy over personal glory. As a spirit, Covinhas possesses notable abilities including the power to possess humans and objects, unlocking a host's full physical potential, though powerful psychics may require permission for full control. He can also perform mass hypnosis and launch energy attacks, such as the Wraither Beam.