I first thought this is just one of those brainless ecchi high school romances. But after 12 chapters, I see that there's more substance here. Each chapter is a stand-alone story about teenagers' love and sex lives, and they're all surprisingly well-written.
The characters - especially the female characters - have been unique and unpredictable. The girls are simultaneously adorable, manipulative, and horny - just like real girls. They're just as confused as the boys when it comes to sex and love, and they don't easily fall into stereotypes. I find myself caring about these characters more because they actually have human flaws.
The sex scenes are tastefully done, and don't feel as gratuitous as I feared, because many of them are actually central to the plot. Sometimes, characters have sex because of love, but sometimes, they have sex because of loneliness, and sometimes, they do it just because they're horny.
The stories don't always play out the way I expected. You see these school kids struggling with their sexual urges, and romantic feelings, and things don't always end well. Some stories are funny (such as the boy who falls in love with a girl who hates sex), but many are bittersweet (such as the story of the boy who falls in love with his step-sister).
Give it a try. You may be surprised.