Alternate terms for something that's not quite soul mates

Allow me to begin by saying that I am a big fan of calling a rabbit a rabbit. But when it lacks some fundamental rabbit quality, say hopping, it does cease to be a rabbit and need to be called something else.

That's about where I am right now. I've been using the terms 'soul mates' and 'almost soul mates' in my notes, but they don't really fit with what I'm doing. And almost soul mates is a bit clumsy and contrived. I'm drawing a blank for alternate terms though.

Basically, every soul is divided into two pieces. The other half of your soul is what I've been calling a soul mate, but it doesn't have the romantic or sexual conotations we usually think of with that term. It's acutally considered a bit narcissistic to have that kind of relationship with your soul mate, because they are literally the other half of you. There are, of course, still people who do it, but it isn't the norm. Usually your soul mate will just be the best and dearest friend you could ever have. It's further distanced from what most people think when they hear soul mate by non-human reincarnation, so your soul mate may not even be human in their current life. I've got one guy in mind whose soul mate is a dog, and I don't really want readers to make assumptions about that relationship that would be completely wrong.

What I've been calling almost soul mates are people you were so close to in a past life that your souls kind of grow together, like two trees that twine together as they grow. Someone who was your twin or your lifelong best friend is a likely candidate, with other siblings, parents, and lovers also possible.

So, does anyone have any thoughts for what I could call these two bonds?

Kindred Spirits?

There's sexual connotations to the term "soul mate"? Since when? O.o If anything, your usage is more correct than that. ;p

So you are looking for something that implied a bond between them, but excluding any possible sexual components?

would Star-crossed do the tricks?
The others that come to mind have already been said xD

Maybe just "Other"? Let the readers fill in the blanks as to if it's other half, other soul, etc- if it's a pretty common aspect of life it would probably have a simple name.

Twin souls? Twin flame?

Perfect fit.

Soul twin? (Totally original and in no way similar to Geesafaire's "twin souls" idea.)

I'd suggest something like "Other half," but that also has a romantic connotation. Maybe something about half and soul? Soul sharer?

You could also use "soul" and another word that's not quite "mate" but gets the same point across. Partner, companion, Co-soul, soul pair. Something like that.

Hmmmmmmmm ok come on ideas!!

Soul's Cousin (like "oh, she's his soul's cousin.")
Dear Heart
Symbiote
Complement Soul

I think Other could work for the main bond. Nice and simple. And I like dear heart, but I will likely use it as more of a pet name than a term to specify the bond. Thanks for all the suggestions so far.

What do people think of using Familiar for the ones who are 'almost soul mates'? Is the conotation of animal spirits acompanying witches too strong, or can I remake it for my own purposes?

Also, does anyone have any ideas for what I could call the quest to find your other? I think that's going to be a big part of the story and the culture, and I feel like it should have a name of some sort.

The relationship between your Others sounds like the Rynax from the anime Phantom Memory Kurau. The Rynax are these beings of energy that come in pairs, who are more or less one half of a whole. A lot of people think the two main girls, Kurau and Christmas are lesbians when their relationship is so much more complex than that and has no romantic/sexual connotations. One of them even gets a boyfriend later, but it's completely different from the relationship they have with their pair, as they refer to it. The main characters are the lucky ones. Most other Rynax that appear are freaking out or going insane because they can't find their other half, or they lost it somewhere.

http://myanimelist.net/anime/483/Kurau_Phantom_Memory

xD I don't mean you should copy them or anything. I just thought you might be interested if you had never heard of it. It's a great show. *Nerd*

To your questions, is this a common thing? Like is it just a fact of life that everyone has an Other, and at some point you go on a journey to find them? I thought maybe it could be like your Calling. As in your other half is calling to you and you feel the need to go find them. That's just an idea.

Why are animal soul mates, almost soul mates? Does it not count as much if it's not human? The idea of a Familiar makes it seem like they're some lesser being, or servant, but maybe that's just me. There's nothing stopping you from recreating the term to fit your needs though. I'm only going by how I've seen it. If you do it right you could even rework the term 'soul mate' to fit your definition without much trouble.

Other Part
Soulfriend
Soulsharer (I feel clever- who would want a romantic relationship with the one who shares your soul???)

Soul Siblings!

Maybe just "Search"? Keeping with the simple theme. Capitalization optional.
As in, what are you doing? Oh, I'm Searching. I still haven't found my Other, I need I Search a little more.

"Search" does not look like a word now O_o

Connatural

They could call each other their "similar", which is like the word 'familiar' but...different? I'm trying to help, really...

As for the quest, you could relate it back to a search for one's whole or true identity. I like the Calling idea, too.