Astral Influx, aka blue flame thingy, associated with
The Target-
Ciro is the rightful owner, as has been fairly well established. Apart from being the first one to touch it, the symbol is
tied to her Soul Overcharge, and also floats above her head. I could cite lots more (and others have,) but I think the above is sufficient.
Reverent Savior, aka hexagon thingy, associated with
??-
Riltia. Sinful mentions ?? has never been online, which is why he does not know him/her. This implies that Reverent Savior is not fully integrated with the rest of the Siblings. Riltia is the only Sibling besides Ciro who seems unaware of her heritage, and shares a similar lust for adventure. In particular, she
does not recognize Oric when they meet face to face. Most conclusively, Ciro
navigated to Riltia by focusing on that symbol, and the only time we actually see Reverent Savior used is
Ciro undoes the doom transformation, which appears to be sort of counteracting a negacharge (you can see her soul charge meter is dark while transformed, but when transforming back it goes to normal, at the same time as Ciro's.) Also, hexagon motif on Locking Glass fits as well.
Illborn Exchange, aka green triangle thingy, associated with, well, nobody-
Sinful. The current working theory for the Soul Stars is that they look like the symbol on
Sinful's screen- The Target is represented by the Astral Influx, and we know the unlabeled hexagon symbol is associated with
Reverent Savior. The green triangle symbol of the Illborn Exchange is unrepresented on Sinful's screen, however. Of the Seven Siblings represented on that screen, only the Rebel is not represented by a symbol- Sinful's face is used instead. Sinful can't call the triangle because the triangle is the Rebel, and HE is the Rebel- can't call yourself. In addition, the Illborn Exchange was first found in the possession of the Chief, and he freely gave it to Al. It seems like the Chief would be unwilling to so casually give up his OWN Soul Star, which means it must belong to someone else. Sinful's biggest grievance is that his Soul Star was stolen from him, and the Illborn Exchange is the only one we've seen that isn't really connected with anyone else. The only other thing connecting them is the color green, though color seems like a weak link indeed.
The next two lack names, but are also seen in the Oversoul segment.
Unnamed Lightning thingy, associated with
the Mechanic-
Proxxy. Apart from being bright yellow and electricity-based, she also
signs her name with the symbol. On top of that, we know from Sinful's exposition that the Mechanic is the First symbol, and lowest on the pecking order.
Proxxy is repeatedly referred to as the First on that big screen throughout the whole befriending Cherish thing, and they also mention that the First has an electrical specialty, which is why her presence is requested so urgently. Finally, the pecking order position is important because Sinful then says " he/she just does what people tell him/her to." You know, as in he/she acts as their proxy. Ha Ha.
Unnamed Red Hammer thingy, associated with
the Thief-
Oric, of course. The Thief is the one who took Sinful's Soul Star and then imprisoned Sinful for defiance. Oric is clearly top dog among the Siblings ("Oric the Awesome and the Six Sinister Siblings") so he is mostly likely the one who set Sinful down. We don't have much else to go on, really-
Oric wears the symbol on his shirt, and we've seen it
on the teleport pads and
in the stars outside the big glowy thing in Al's flashback, presumably the Warrens. It doesn't mean much other than the Hammer is closely associated with somebody who has a great deal of control/influence in the Warrens, and that means Oric.
The last two lack names and are
only seen and interacted with in
Sinful's Intermission.
Eyeball thingy, associated with the Eye-
Floe. Sinful
calls her by name, and because her gender is confirmed female I'm chalking her up to the only
random, unidentified woman we've run into. Her symbol shows up nowhere else, we've seen no abilities (beyond "big honking gun" if Floe is indeed the random chick,) ...that's really all we have to work with here.
Sound Wave/Mike thingy, associated with the Voice-
Chief. At the same time Sinful confirms the Eye/Floe to be female, he also sets
the Voice as male. The Voice is a "lazy, condescending asshole" and is in charge of communication, and is apparently good at the "code," whatever that is. So when I think of lazy, condescending assholes,
I think of the Chief. His robe is covered in crazy symbols (much like Ciro Reborn,) he has a Soul Star (Illborn Exchange) to give Al to help on important, security-threatening quests (loss of power to Underside,) and he is quite familiar with the Greens, instructing Al to do things there (did we ever figure out what the LSS is?) The Greens is where that crazy coded communications thing was, which fits with the Voice's duties, so that's a tentative connection. Really, a lot of this is chance and happenstance, but we know the last Sibling is male and there aren't many other options.