Kiichi Furano hails from Hokkaido, Japan, embodying a slow-paced, peaceful existence defined by his love for food and a characteristically heavy build. His gentle, caring nature persists alongside notable gluttonous tendencies, complemented by an exceptionally robust digestive system capable of enduring even Sapphie's notoriously poor cooking. Furano possesses practical skills in sumo wrestling and haiku composition, alongside reliable proficiency in household chores like dish cleaning.

Recruited as the final member of the KiraDeco 5, he operates under the codename "Slow Life Yellow," a reflection of his tranquil lifestyle and yellow-themed aesthetic. Stationed in Jewel Land for his mission, he resides with the Jewelpet Sapphie at her bookstore, aiding her with daily tasks and responsibilities. This includes ensuring punctuality for group activities, such as escorting Sapphie to outdoor school sessions when she runs late.

His character development culminates later in the series when his strong protective instincts toward others forge a profound emotional bond with Sapphie. This connection directly manifests as his Jewel of Fate, the Yellow Sapphire, enabling his transformation into an enhanced form through his unwavering commitment to safeguarding his companions.

After successfully concluding the mission to collect Deco Stones and avert eternal darkness, Furano returns to the human world. His departure is marked by preparing a final meal for Sapphie, symbolizing their enduring partnership.