This is a light drama series about a group of friends from a middle school tennis club who are now in their early 20s. The group meets up for a reunion at a mansion and other events around town. Along the way couples are formed and broken. In all its a good story and well suited for watching as a couple for a romantic story. There are no big thrills in this one, it is a very light story and is more about the characters and their search for love than anything else.
As for the H rating, I do not see it. Each of the four episodes has one single love-making scene in it, and it is pretty much PG13 or maybe a Light R rating at the most. Everything is done under the sheets and there is no hardcore content of any kind. You see more H in your average made-for-cable series.
All in all, it is a good series, and a pleasant watch. My only complaint is the way it ends, the producers must have meant for it to continue on because you are left with unresolved issues.