Aphantasian

Aphantasian: Aphantasian is a type of headmate who doesn't exactly have a role, and are rather an aspect. Aphantasian headmates aren't fully formed, and probably never will be. System members can sense their existence, but can't see them. They can only be viewed as frames of a person, blobs of colors, as shadows, or as smoke or light wind. Touching them is like feeling static, and they have no smell. They can either speak clearly or in whispers, almost like they're far away.

Aphantasians have fully formed thought processes of their own and are individuals of their own. But, they may have trouble learning, understanding, moving around, and speaking. And, are incapable of fronting.

Aphantasians can easily get mixed up with delusions, and it can be hard to decipher the two. But, the best way to tell the two apart is that aphantasians let out an empty feeling, as if their existence is trying to fill the space but it just can't.

Headmates can be formed like aphantasians or slowly become less grounded and eventually turn into an aphantasian.

It is not yet documented if headmates can come back from being aphantasians.

Etymology
The word "aphantasian" is derived from the word "aphantasia", which is often described as a visual condition, multisensory. This is when people experience a lack of mental imagery, and, in resut, have a reduced capacity to access other mental senses (imagining sound, movement, smell, taste, and touch). This perfectly fits the concept of an aphantasian headmate due to its faded presence.