Loved it!
Great picturing of (soft) sadomasochism. Contrary to lots of SM stereotypes I've seen in BL, the relationship is healthy, both M and S are very well-written characters, the author doesn't go ridiculously over the top just because most people expect it from sadomasochism, it actually feels very real.
So, that was very refreshing, as well as the fact that the M is actually the one to instigate the relationship, and that he's also teaching his seme (that definitely has the potential XD) how to be a good S. ^_^
Oh, and the sex is hawt. If you just need one easy reason to read this, then just read it for the smut. It's worth it.

Well, the first thing you have to know is that it's based on SM relationships. But the way it's dealt with is light, so even if you aren't into it (like me), you may enjoy this story, because even though there's SM elements, love is still the main point in this story. Unlike some other of her works, the plot is well constructed, and not only a support for smut stuff. I liked how sensei showed the evolution of the seme who's discovering his own sadist side, and his interrogations. The art, as always with Kanzaki sensei is really great, and the sex scenes are really hot and sexy. So it's a good and entertaining story, but maybe a bit too short for the plot to get as deep as it could be.

On the other hand, the second story isn't really catchy. The realization of the main character's feelings doesn't feel real, and it feels more like they're just craving for sex. So it's just good smut.

In the end, if you want to try an SM story, this one could be a good one to do so.

Definitely read both prequel stories before this one!

That said, I liked all 3 volumes. They were interesting enough, with likable characters and a good dose of smut. Most interesting here are, typical for Kanzaki Takashi sensei's work, love triangles and S&M content. I think she does a very good job portraying both those topics, maybe not realistic but entertaining!
I personally don't always like love triangles or polygons because oftentimes the characters come across as slutty, careless or just "okay with everything" - boring and like they have no personality.
Her love triangles often have lust, conflicting feelings and sexual tension.... it's done pretty well.
The SM plot here is what I really like.
It's great to see the point of view of a guy who originally has no interest in that, but liking the masochistic Hasebe, he thinks about if he can be the kind of sadist he needs in bed.
I enjoyed this approach because normally in yaoi there's just always an S seme and an M uke without ever any mention of that sexual preference or whatever, it just is.

I'd recommend this to pretty much anyone who looks for a smutty story, even if you're not strongly into SM because that's really not too specific, and you certainly don't have to be all into it to like this story.