Daisuke Chinen is the younger brother of Trinity dance unit leader Miyuki Chinen. He attends Yotsuba Junior High School as a second-year student, sharing a class with Momozono Love and Higashi Setsuna. Physically, he possesses short, light brown hair and brown eyes. His typical attire is his school uniform, while casual wear features a red top layered under a black jacket, light blue jeans, beige sneakers, and a necklace. Personality-wise, Daisuke maintains an average demeanor but frequently attempts to project a cool image, especially around Love. He can be occasionally brash and hotheaded, yet balances this with a genuinely kind heart and a strong protectiveness towards his friends. He harbors a significant fear of thunder, which causes him visible distress. His surname, Chinen, reflects his Okinawan heritage and birthplace on Okinawa island, while his given name, Daisuke, combines the meanings "big" and "tender."

His relationship with Love Momozono is close yet complicated, marked by his longstanding romantic crush on her. Love remains largely oblivious to his feelings throughout much of their interactions, which often involve playful bickering and arguments despite a foundation of mutual concern. He confides in Cure Peach about personal matters, unaware she is Love in disguise. With his sister Miyuki, he shares a positive dynamic, though he finds her teasing about his affection for Love embarrassing. Miyuki occasionally leverages her influence to assist him, but carefully avoids excessive requests. Daisuke's closest friends are Sawa Yuuki and Mikoshiba Kento, who both have crushes on Miki and Inori respectively. The trio frequently collaborates, including forming their own dance group.

Key events involving Daisuke begin during an amusement park visit where he tries, but fails, to invite Love to a Trinity concert due to a Nakewameke attack and her existing plans. Later, while preparing a haunted house for the school festival, a falling skeleton prop triggers an argument after he accidentally touches Love's hand and panics. During a rainstorm, he follows her back to school out of concern, helps repair a damaged prop, and reveals his fear of thunder. Love responds compassionately, crafting makeshift earplugs for him. When Westar transforms the skeleton into a Nakewameke, Daisuke attempts to shield Love, inadvertently blocking her transformation. Cornered by the monster, he refuses to abandon her despite her pleas, though his fear of thunder ultimately causes him to faint.

On a school trip to Okinawa, his birthplace, Daisuke actively avoids arguments with Love, hoping to create positive memories. Spotting her entering woods at night, he follows out of concern and witnesses Cure Peach battling a Sorewatase. He rescues Peach from the ocean and confides in her about his efforts to reconcile with a friend; Peach wishes for his reconciliation with Love. The next day, while painting Shisas together, they resume arguing, though Setsuna observes their compatibility. The trip concludes with them captured happily together in a photograph.

Inspired by Miyuki, Daisuke forms a dance group with Yuuki and Kento, intending to confess to Love if they win a competition. After their elimination, he vents his frustrations and confesses his romantic intentions to Cure Peach, still unaware of her identity. Following the revelation of the Cures' identities, he realizes his confession was made directly to Love. Before the final battle against Labyrinth, Love seeks to address his feelings, but he insists she respond after returning safely. After the Cures' victory, he asks for her answer; she playfully refuses to respond, leaving him momentarily baffled before he smiles and cheers for her dance performance.

Additional trivia notes his given name is shared with other franchise characters and highlights the significance of his Okinawan heritage.