In a certain wealthy household, two men lived together: a strict father and his reclusive son. The house employed a maid to take care of their daily needs, a 20-year-old newcomer named Anna Oguri. Still inexperienced and filled with anxiety, Anna struggled through each day. Yet, her earnest and endearing nature gradually touched the hearts of both father and son, bringing warmth into their lives. One day, the master of the house suddenly began wearing a strange mask, refusing to speak or move. The only person who knows the true reason behind his bizarre behavior is Anna, the sole maid. What caused this strange turn of events? The answer lies in Anna's overly kind heart. To uncover this secret, one must delve into the deepest corners of her mind.