Hey so this Miki arc Will also involve Momo and probable Hajime as well.
I remember in the early volumes there is an art of the sisters with dolls of each others, like Hima has of Yori and Shiho has of Aki, makes me wonder if at some point their relationship was going to go into a diferent direction.
I hope eventually we get some kind of scene where Miki shares some of her one-chan's photos with Shiho, like maybe despiste how she feels abouth the situatión, she finds that she is happy seeing how much Shiho loves Aki, and maybe teases her with her exclusive album