A story set in a quiet hot spring town during late autumn, depicting the forbidden emotions that arise between a mother and son. Heruaki, the son, has long harbored romantic feelings for his young and beautiful mother, Sakiko, but has never dared to confess them. However, his inner turmoil and longing grow stronger each day until he can no longer suppress them. One day, during a hot spring trip together, Heruaki finally reveals his true feelings: "I've always loved you, Mother..." Shocked and conflicted, Sakiko finds herself unable to resist the storm of emotions, and ultimately shares a kiss with her son. This tale explores how the boundaries between them blur under the weight of what they call love, and what consequences follow. Against the backdrop of a tranquil onsen town shrouded in warm mist, a strange and forbidden affection begins to bloom between mother and son.