Core Viewpoint - The article reflects on the struggles and nostalgia of adulthood, using the metaphor of childhood experiences and the product AD calcium milk to illustrate the contrast between past innocence and present responsibilities [2][4][23]. Group 1: Childhood and Nostalgia - The author reminisces about childhood memories associated with AD calcium milk, highlighting the emotional connection to the product and its representation of simpler times [4][20]. - The narrative evokes a sense of longing for the carefree days of youth, contrasting them with the burdens of adult life, such as work pressures and familial responsibilities [12][23]. Group 2: Adult Responsibilities - The article discusses the pain and challenges faced by adults, symbolized by physical discomfort and the metaphorical "甲方" (client) representing external pressures [2][12]. - The protagonist's struggle against various life pressures is depicted through imaginative battles, illustrating the internal conflict between aspirations and reality [11][21]. Group 3: Transformation and Resilience - The narrative culminates in a transformation where the protagonist seeks to reclaim lost dreams and confronts the challenges of adulthood with renewed vigor [15][18]. - The use of fantastical imagery, such as turning AD calcium milk bottles into weapons, symbolizes the fight against life's adversities and the desire to overcome them [21][23].