This must be one of the worst manga I've read in a very long time. Don't get me wrong, I love many of Nagai Go's series, though I don't read his work all that often anymore. I even have physical copies of some of them in languages I don't know. But Kamasutra is just terrible. And its terrible for all the reasons his other books are great. Because, it is the typical Go Nagai schtick but this time set in India and instead of gruesome violence and murder, there is explicit sex. Loads of it, even sometimes with genitals.
There is sex, but it isn't sexy at all. Rather, it is childish, filled with idiotic jokes, and characters making stupid faces. And by filler, I mean, every single chapter has at least two or three scenes like that, some scenes even including gerontophilia, bestiality, and others. Oh, in "good" Nagai Go fashion, it is also racist and misogynistic. The women, all of them without any exception, are presented as sex bombshells, annoying horny girls, or empty vessels for the male characters' seed. Or an amalgam between the three. The male characters are not much better - they are either sexgod superheroes or inane oversexed butts of jokes. The latter, of course, are drawn as small and weak people. One of them is even Higegojira from Go's classic sex comedy Harenchi Gakuen.
This all begs the questions, for what audience was this thing made? Was it for teenagers, like most of Go's other work? Though the sex and jokes might make it seem so, the numerous pages with direct quotations from the Kama Sutra make me feel like it wasn't. After all, would children, even teenagers, would be interested in reading pages upon pages of long, boring passages of an ancient Indian text with minimal illustrations? Also, would they be into the main theme of the original text, pleasuring your partner, and the ultimate, haphazardly slapped one of the manga - procreation for the sake of humanity's existence? Can't be certain, but don't think so.
On the other hand, I can't say that it's made for grown readers, either. There are just way too many childish sex jokes, horny, predictable plot twists, and overall immaturity of the thing to make me feel like it wasn't. But, again, that's Go's entire thing. He's been doing pretty much the same thing, rehashing the same tropes for who knows how long now.
Visually, it's also 100% Go's style. Characters that look like they came straight from 70s shonen manga, static-looking action scenes that finish way too fast, uninspired panelling and page design. All stuff he can probably do in his sleep, and reading these volumes, I couldn't but feel that he did just that.