This manga is horrible. Do yourself a favor and support the anime and hope we can get an official NOVEL translation.
The story has been significantly dumbed down in favor of fanservice. Honestly, I do not mind the shows of lesbianism because they are present in the anime. However, this adaptation exaggerates the femalexfemale relationships while completely eliminating the malexmale ones.
You may argue that the relationship between Saki and Maria is more important than the one between Shun and Satoru. But there is no reason to have several pages dedicated to showing their naked (underage) bodies rubbing against each other.
If the anime confused
you, go ahead and check this out. But honestly, it's not worth anyone's time.