From Keygemin Wiki

Setting is a process of metamorphosis from Gemin into Keygemin. In order to set a gemin, its possessor must convince that gemin to manifest. It does so only at its own volition. Setting requires a gemin to be pushed against a material in order to start the process of transmuting the material they are being set within.

A Keygemin will typically only manifest when exposed to a material of its preference, which aligns with its Aspect and Disposition. A White Keygemin may desire materials such as fine stone such as marble, silver, or gold. Others, such as magenta aspect gemin, may have no preference of set material, allowing themselves to be set into refuse, manure, or rotting meat.

After the setting process is complete, the Keygemin will be a golem which takes a form aligned to its aspects. Its physical appearance and demeanor will reflect its current emotional state. Difficult to control or handle aspects, like blue or red, may cause the setting process to be unbeneficial to the gemin possessor.