This couple went under my radar.
For a full review of the anime these two girls are from, click here.
So Ao and Kotoha. Long story short these two are like a toned down Yume and Yuuki from Kanamemo with superpowers. During the first half of the show it is made as clear as a sunny day that these two ladies are a couple. Whenever the two are together on screen their bond is undeniable. This changes in the second half however. While their relationship is still there how the two show their bond becomes more subdued. Basically, had it not been for their cute and great moments in the first half this would be a simple ship at best. It becomes that toned down. Keep in mind Hana no Uta is a retelling so whether the two are a couple in the manga or at the very least hinted as being one is unknown to me. Viewers who know please keep it simple. I do not need a truckload of details.
As for the Akina, Hime and Touka love triangle, meh.
Oh and some would probably ship the two girls featured in the second half. Feel free.