SS Sisters aka Super Sadistic Sisters is about a guy, Kenji, who gets turned on by his sister torturing him. Since she enjoys doing this, you can imagine what happens. Comedy, ecchiness and tons more.
I'm gonna be honest here, I enjoy this manga. It gives me laughs and is a pleasant read. It's ecchi, really ecchi, but I don't mind that. I happen to enjoy it. It has a comedic sense which I really enjoy. I don't really know if it's just me, but many of scenes just crack me up.
If you're looking for something to read during the night or if you're just looking for an ecchi manga, you've got it here.
