Chihiro Sakai is a first-year university student and a member of the men's college cheerleading team DREAMS. She has upper-back length brown hair that is typically tied in a ponytail, with bangs hanging over her forehead and neck-length strands framing either side of her face, paired with dark gray eyes.

Chihiro has a sweet and kind personality, though she can also be rather silly at times. She is notably clumsy, often talking about how she has hit her nose during practice. While she is committed to successfully completing her cheerleading routines, her clumsy nature makes this difficult, as she is very much still in the learning process.

In the story, she is established as the girlfriend of Koji Tono, a fellow member of the cheerleading team, with their relationship being revealed in the eleventh episode. The pair have been dating for quite a while prior to this reveal. Her relationships with other members of the team are also touched upon; for instance, her consistent kindness leads another team member, Haruki Bando, to mistakenly believe she had been flirting with him, when in fact she was simply being nice.

Due to her role as a supporting character, detailed information regarding her personal motivations, significant character development arc, or notable cheerleading abilities is limited. Her primary function within the narrative is in relation to other main characters, particularly her romantic connection with Koji Tono and her friendly interactions with Haruki Bando.