This oneshot actually surprised me with its melancholic themes and mood. I was expecting some fluffy yuri, but it turned out to be a story about the effect on children of a strained relationship between the parents. It's pretty good; not much to complain about considering it's a roughly hundred page oneshot which I read in around fifteen minutes. If you want to know the ending beforehand so you don't get surprise tragedy'd, I will tell you. The twin sisters do something unholy in bed, and they get found out by their mother. Now, I don't know much about philosophical meaning, so I think it's just that.
TL;DR: Read this oneshot if you aren't looking for some feel-good yuri story and don't mind some drama and a sad undertone.