Reviewing Hentai manga is conflicting, some series are peak like Shokugeki and some are.....beyond redemption? This one is just in the middle of acceptable yet skeptical Right off the bat you instantly see there is no blood relation, it seems the sister is on the path to failure being prey to men for her looks and figure. The main brother of non blood relation makes the resolve to get on good terms with her? Simple story for any step sibling manga, but that's only the initial impression In no time whatsoever, readers will instantly see the "sister" is prone to being lied, manipulated, controlled, etc. To thepoint where any of us could uh... do it and turn her into our personal plaything. This is something I realized deeply after reading the parallel NSFW direction of the story here. The author is utilizing top tier Hentai Art with larger than usual but natural proportions to bring emphasis on certain areas.

Worth reading? Well at 51 chapters there is only minor development, but the MC brother isn't entirely cool himself. He is at conflict with his feelings and it doesn't help another extremely attractive classmate is gunning for him

For those not familliar, Kuso B is a manga work with hentai direction alternatives. They are not related in any way whatsoever, as it was confirmed this is the main story.