Nosaki Futago is the elder twin sister, her name originating from the Japanese phrase "futago no saki" meaning "the elder twin." She attends middle school with Bocchi Hitori and is intrinsically linked to her younger twin, Notsugi Futago, who calls her "Saki." A quiet voice distinguishes Nosaki from her louder-speaking sister, a consistent trait in their interactions. She participates in group activities like a cooking class alongside Bocchi, Kurie Ito, and Peko Onaka. Bocchi's growing ability to tell the twins apart leads to her formally befriending Nosaki, marking progress in Bocchi's efforts to connect with classmates, including those initially seen as a unit.