Colitas, known in the original Japanese version as Ribon-chan and in English as Bijou, is a character defined by her grace, her affectionate nature, and her one-sided romantic feelings for the main character, Hamtaro. She is a small, white-furred hamster who is easily recognized by the large, distinctive blue ribbons that hold her fur into two pigtails, an accessory she treasures dearly.

Her background sets her apart from many of the other hamsters in the clubhouse. She is originally from France and moved to the neighborhood with her owner, a girl named Maria. This origin is often reflected in her demeanor, as she carries herself with an air of elegance and refinement. In the English adaptation of the anime, this is represented by giving her a pronounced French accent, and in the original Japanese version, she often ends her sentences with the unique verbal tic "dechuwa". Despite her somewhat unworldly and tidy nature, Colitas is not a fragile character. She is consistently shown to be generous and helpful, willing to get dirty or messy if the situation requires her to assist her friends, proving that her grace is matched by a strong spirit of camaraderie.

The central pillar of Colitas's character and her primary motivation throughout the series is her deep and persistent crush on Hamtaro. From the very first episode, her affection for him is hinted at, and it grows stronger over time, particularly after moments of kindness from him, such as when he compliments her ribbons. Her primary role in the story is often driven by this affection. She frequently tries to spend time with Hamtaro, and in several episodes, she attempts to go on what she believes is a "date" with him, only for the oblivious Hamtaro to misunderstand the concept and invite the rest of their friends along. This unrequited love becomes a source of both gentle comedy and heartfelt moments, as she competes for his attention in events like a Valentine's Day battle against other interested hamsters like Sparkle and Oshare. While Hamtaro cares for her deeply as a close friend, his childish outlook on love means he remains completely unaware of her romantic feelings.

Beyond her relationship with Hamtaro, Colitas has a number of other significant relationships that help define her place in the Ham-Ham clubhouse. She is best friends with the other main female hamsters, Pashmina, Penelope, and Sandy, and the four are often seen together, sharing a strong and supportive bond. Her dynamic with Boss, another leader among the Ham-Hams, is one of unreciprocated affection from the opposite side; Boss has a huge crush on Colitas, but she is completely unaware of it and appears to view him as a kind and reliable older brother figure. A notable moment of development for her occurs with the introduction of a hamster named Lapis. When Lapis gives Hamtaro a kiss on the cheek, Colitas becomes intensely distressed and jealous, viewing the newcomer as a rival. This storyline resolves when Colitas learns the kiss was simply a thank you, allowing her to overcome her jealousy and become close friends with Lapis, demonstrating her capacity for personal growth and emotional maturity.

In terms of abilities and notable moments, Colitas possesses a more subtle set of skills. While not defined by a single special talent, her willingness to help is her greatest asset. In the fourth Hamtaro movie, she is chosen to be the Snow Princess, a role that requires her to perform a sacred prayer ritual to restore snow to Aurora Valley. When she is kidnapped by pirates intent on stopping the ritual, she does not simply wait to be rescued; her predicament becomes the central driver of the plot, showcasing her importance to the Ham-Hams as a whole. In earlier media outside the main anime series, she was also depicted as having an interest in knitting, crafting fluffy sweaters for her friends, though this trait was later given to a different character in the show.