This is a nice, simple guide to anatomy which is perfectly suited to the Manga artist, who has very specific requirements about what they want to draw and how they want to draw it. Its content is absolutely summed up in its title.
And that’s all I really need to say, except that, if you’re not a Manga artist, it’s also worth more than a cursory glance because Christopher provides a basic guide to drawing figures for people who don’t want to draw figures. How so? Well, let’s assume that you’re not looking to produce muscle-accurate representations of the human form, but rather to include figures in a painting and have them not look like statues or waxworks. As long as they’re convincing, they’ll pass muster.
If that’s you, then this has much to recommend it. True, you’ll have to get past the big-eyed kids that are the staple of Manga, so you may need to do a bit of work of your own on faces, but, apart from that, you get nice simple instructions and demonstrations of male and female figures in a variety of poses and moves that you should be able to adapt for more general purposes. It’s important to emphasise “adapt”, because, if you don’t think you’re capable of a little lateral thinking, you may struggle. If you think you’re up for it, though, you’re quids in.