FWIW, Alira’s the one (not Ciels) who does most of the fighting with Simon/Suzane in the conflict scene you mentioned earlier. And she’s the one who finds Horion and Linos in the framing story for Ch 3. But yes, she’s not an NPC who gets much focus.
And she mainly shoots Theurges in Ch 4, not Plektoi.
The characters I’ve listed as bi have all grown up in cultures with a binary concept of gender (i.e. everyone except the Nyr and Abhumans), so their initial self-conception is “attracted to either/both.” They’ll respond in different ways to potential nb ROs. Abelard will cling to the binary; in general, he’s uncomfortable with the idea that any of his paradigms are arbitrary. By contrast, it won’t make any difference at all to Yebben. And Elery experiences attraction on a highly individual basis, and (when she begins to meet them) will find that includes nb characters.