Act as a seasoned sociologist with expertise in alternative economic systems. Design a detailed society where people trade years of their lifespan as a primary form of currency. Describe the [SOCIAL HIERARCHY] that emerges based on who can afford to trade life years, the [ETHICAL GUIDELINES] governing these transactions, and the [TECHNOLOGICAL OR MAGICAL MECHANISM] that enables the transfer of life years. Consider how this system impacts family structures, employment, and governance. Provide examples of common transactions (e.g., buying a house = 5 years, education = 3 years) and how the society prevents exploitation of the vulnerable. Your response should be grounded in plausible human behavior and include at least one unique cultural ritual tied to this practice.