The first thing to know about the Strawberry Panic! manga is that it does not have an ending. I've bought the "complete" manga collection for it which shows all the chapters the series has, but alas there is no ending.
Strawberry Panic! is a manga taking place in Astarea Hill with three competing girl's only Catholic schools. The main character Nagisa Aoi ends up transferring to one of the schools in the area called St. Miator's academy and ends up having the most popular girl in school called Suzuma having Nagisa in her sights. How does this yuri play out?
Let's just say the whole story wasn't very interesting, you barely got to learn any back-stories to the characters. The story luckily had a very big amount of relationships displayed between the characters especially with the conflicts between members of the different schools on Astarea Hill as they compete for the "best couple" title for their school.
Everything in this series has to do about relationships between the girls in the series but the relationships are poorly developed. Most of the relationships are developed by a girl being forced into a relationship with the other partner being very dominant. I could assume this would be to try to make the manga be provocative but either way it leads to a poorly designed story and pretty unlikeable characters.
The whole main idea of the series is that there is an annual "best couples" tournament between all schools at Astarea Hill and each school is very serious about winning it (now do know, that there are only girls only schools on Astarea Hill) and all the popular girls from each school force a girl they like to enter with them. So these relationships are very very new while trying to show everyone why they are supposed to be the best couple. Without development this story is pretty awkward and not enjoyable to read at all.
The whole manga felt like someone wanted to make a yuri with dominant girls and had to come out with a plot pretty damn quickly. With no authentic characters, no ending, no real half decent plot and with no real anything to give this manga a frame, there is no real reason to pick up Strawberry Panic! unless you are a very serious yuri fan who wouldn't mind only reading the manga for the drawings of dominant lesbians.