In the globally popular VRMMO, Infinite Dendrogram, players' abilities evolve based on their actions, personalities, and playstyles through a system called Embryo. The game features incredibly realistic NPCs called Tians. After finishing college entrance exams, Ryohei Ryokutori, a young man starting his life alone in Tokyo, begins playing Infinite Dendrogram, a game his older brother introduced him to. This is a story about a world, a game, and cherished memories.