From Citizen Sleeper Wiki
The Seed is an item players encounter throughout gameplay of Citizen Sleeper.
Description[edit]
The seed is an item given to the Sleeper by the Gardener. Its principal use is to grow an interface for the Greenway Data Cloud. The gift is given at the end of NeoVend's questline, and allows the player to sever the connection between their mind and body and live eternally within the Data Cloud; thus, this occurs right before a player completes Citizen Sleeper and is one of the reasons that NeoVend's questline is the last to be completed by players.