An affinitype is a unit of identity our system uses in which one has an affinity for something or a strong connection to it, but that connection is not better represented by words like kin, synpath, or any other words one can think of.

To give an example, Vyvian has a strong affinity for hamsters due to his history of keeping them as pets. People frequently associate him with hamsters and even equate him with them. However, Vyvian is not a hamster therian, and he is not even synpath with them, in that he does not consider himself to identify WITH them instead of AS them. They're just something he considers important to him and is a part of his identity, but not by way of him being a hamster himself.

To give another example, forests are important to Perpetua and how he experiences his identity and alterhumanity. He has kintypes that relate to forests, like cryptids and creatures. However, Perpetua does not consider himself to be part of a forest, at least not in the way that the trees or rocks or streams are. Forests would therefore be something he has an affinity for that are an important part of his identity, but he would not consider his connection to them to be that he identifies as or with them.

Some people would say that affinitype is inherently covered under "synpath", but we don't see it that way. We see "synpath" as being similar to otherkin, but where you identify WITH something instead of AS it.

We don't feel that the phrase "identify with" is just a generic way of describing having an identity relating to something, though. We experience "identification with" something as an identity in which we see ourselves as similar to that thing, see that thing as an extension of ourselves, or understand ourselves through that thing. In other words, our identification with that thing is still represented by the phrase "I am this thing".

Some units of identity, however, do not work like that. Some of them are more like "I like this thing" or "I engage with this thing" or "this thing influences my attraction" or "this thing affects other things that I am". We do not feel that the word "synpath", at least as we experience it, covers these identities, and vesility doesn't always cover it, so we use the term "affinitype".