Saki Satô, 36, is Ichiro Satô's mother and Kana Kojima's childhood friend. She actively champions the romance between her son and Kana, driven by her own past: she began dating a teacher in high school, married him upon graduation, and welcomed Ichiro soon after. This experience fuels her support. Aware of Kana's strict teacher reputation, Saki sees her genuine affection for Ichiro and orchestrates opportunities for them to bond. She invites Kana to their home and engineers non-school interactions, even exploiting Kana's low alcohol tolerance to lower inhibitions and spark intimacy.

Saki employs playful persistence in her matchmaking, often ignoring social boundaries to push the relationship forward. Her involvement blends support with meddling, rooted in her positive history with a similar dynamic. She lives with Ichiro and her younger daughter, Shio Satô, consistently serving as the central romance's facilitator throughout the series.