Now this is interesting. They make sense in their respective contexts: Towako can only see beauty when there is stasis (eternity), while Yukina sees beauty where she makes it (moment); and then we have Haine who surpasses Aika, being from the same family/same plant and all.
But what about this one?
Asuka - Asuka (pseudo) ; Mikaze - Hagidzuki (pseudo) > Kachoufuugetsu (flower, bird, wind, moon), "the traditional themes of natural beauty in Japanese aesthetics."
At first I had assumed this:
For the rest, we have Sakurada Asuka and Hagimoto Mikaze, "sakura" being the cherry blossom (obviously) and "hagi" being the Japanese clover.
and looked for any sort of folklore or story or allusions in which cherry blossom and clover opposed each other.
But now I realise that, from volume 6 onwards, it seems that there's a trend of the names taking on much more metaphorical meanings than they previously were. Take the whole morning/day/night interplay of the polyamory trio, for instance. Amane and Nina are the opposites at first, and have Ryou come between them; comparatively, Nina and Ryou's online handles are opposites of each other (midnight and midday, respectively).
Cue volume 7's "bluer than blue, bluer than you" thing between Aika and Haine; volume 8 fully plays tiger against dragon with Hikari and Nagisa, even bringing in a huge rivalry between the characters to complete the metaphor.
But where does that leave us now, with the "traditional themes of natural beauty in Japanese aesthetics"? Are we regressing back to the "just opposites" feeling of previous volumes, or is it indicating deeper meaning, truly putting the "meta" in "metaphor"? This is getting me hyped for the next chapter!
Chizumi Fan, Lyendith, thank you both for all the research! Very much appreciated.
