An HIKCharacter contains all the information required by HumanIK to define a character:
the Nodes used in the character's skeletal hierarchy.
the default characterization pose that defines the character's geometry.
degrees of freedom assigned to each Node, if any.
a parent offset assigned to each Node, if any.
The exact byte size of an HIKCharacter object depends on which joints the character uses, and whether it has allocated memory for parent offsets and DoF are allocated. See ~{ HumanIK Objects and Memory Management }~.
You can move HIKCharacter objects freely between memory locations, or send them to another processing unit through DMA.