One day, Hiroshi's father introduces his new wife, Sae. Hiroshi's beloved biological mother, whom his father adored, had passed away five years earlier from illness, and Hiroshi still hasn't recovered from the loss. In an attempt to heal this pain, his father decides to rebuild the family. However, Hiroshi begins to feel intense resistance toward Sae, whom he now must accept as his new mother, and overwhelmed by emotion, he gives in to impulsive actions. The story captures Hiroshi's inner turmoil and the emotional conflict surrounding family bonds.