In folklore, a cambion is a creature that is half-human, half-incubus/succubus/concubus.

It is difficult for us to find information about cambions, even though they are somewhat known to pop culture. Our concept of a cambion is therefore effectively a concept that is similar to a concubus but that has an inherent degree of simultaneous connection to and disconnect from humanity.

A cambion headmate in our system may be a cambion instead of a full concubus due having some connection to humanity, human families, or human cultures in some way. They may also represent our frustrated feelings with feeling in-between certain things.

A cambion who suffers over feeling a total disconnect from humanity will feel differently about it from a concubus who feels the same disconnect, as a cambion has more reason to feel that they "should" feel human, so this would tend to apply to a cambion headmate.