In the small closed world, he buried the seeds in his heart into the soil and small flowers grew. Just send the flower to the outside world and a new flower will come back. It is a flower that is different from the one you grow yourself and can bring warmth to the world. Everything was so safe and comfortable, and he lay there, looking at the bright sky. The world will always be warm like this, at least that's what he believes. Until one day the flowers stopped coming, and withered, he decided to look for answers in the outside world.