Muzan Kibutsuji, a nobleman from the Heian Period, was born sickly and required constant care. His condition prevented him from spending extended periods in the sun, leading to a reclusive lifestyle. Irritable and difficult to be around, he had no friends. As his illness worsened, he could do nothing but lie down and contemplate his deteriorating health. Despite having a doctor treat his symptoms, Muzan found himself sitting at the edge of the porch, gazing at the sun.