#cyncest

Between the two, Uzi for sure. Poor girl has to live with her tail hitting on her at any given moment. It's easier for Nori to ignore or deflect the comments since she isn't with Cyn 24/7. Uzi would be desperate enough to try it, but only when alone.

However, first one to ever flirt back with Cyn is N. Uzi and N would be on a date, and he'd be having fun flustering Uzi with cute flirtatious comments. Cyn is still in love with her big brother, so she often tries to hit on him too. She makes a flirty comment to him, and before Uzi can even shush her tail, N flirts back unthinking.

Silence for a second.

N looking proud of himself for the flirty comeback. Cyn blushing and speechless. Uzi staring at N with the most "What the actual fuck" look ever. Uzi finally breaking the silence to flip out on N for flirting with the demon tail that nearly destroyed the entire universe. N is panicking because he just flirted with the demon tail that nearly destroyed the entire universe, unable to help himself cause tail cyn just looks so cute and harmless like that and it felt natural to forget all the war crimes in the moment and be sweet back. And Cyn had retreated, still too flustered to butt in.

Eventually Uzi gives it a try to flirt back when she's alone with Cyn. And N was right, it felt easy to complement and fluster the demon tail. So she does it more often, until Cyn is less flustered and more emboldened by it, and only amps up the flirting, cause "her gf is finally loving her back". And Uzi is learning to love it.

Uzi is too embarrassed to flirt with Cyn in front of others, but when she hiding in her room with Nori for a bit of intimacy, Cyn pops up and is extra incessant about the flirting. Uzi tries to ignore and dismiss Cyn, but she calls her out lovingly in front of Nori for some of the flirty comments she's made as of recent. Uzi's flustered reaction is damning. And then Nori is flipping out on Uzi for flirting with the demon tail that nearly destroyed the entire universe.

Eventually, after a few more dates with Uzi, Nori relents and also starts flirting back with Cyn, finding herself enjoying it too.

Cyn is an eldritch nightmare robot girl who slaughtered Humanity and also eats whole planets... and is completely obsessed with her adorable soft boy big brother N. They started off as scrapped robots who were taken in and repaired by rich Human girl Tessa, only for Cyn to eventually snap and kill her elitist asshole parents and all the guests at one of their parties, before continuing on to wipe out the entire world. N is at first a loyal murder bot, but over the course of the series begins to rebel against and realize the horror that he and his sister have done. Every time he dies/she kills him, she keeps backups of him and likes to maintain his personality intact because she's so attached to him.

SPOILER ALERT but the show just had its big finale, where Cyn and the main character Uzi (who is N's girlfriend) merge into one person. And N is still with her/them in the end! So they're sort of canon endgame, which is fun.

For prize artwork if they win how about the merged Cyn/Uzi seductively stroking N's chin, with her wings and/or tendrils wrapping around him (and him looking all shy and nervous), saying "I'm not just your sister anymore".