Mattel She Ra doesn’t have a very articulated torso. There’s a ball joint under the bust, but she arches her back much better than she hunches. In fact, you can’t get much more than 90 degrees of forward bend.
I took this picture after modding her, but it demonstrates her default forward slouching capabilities — i.e., none.
I thought of hacking her apart at the waist and adding a torso joint, but then I decided to break her at her existing joint and mod that somehow. Fortunately, when I snapped her apart, she came apart neatly and cleanly. The under bust ball popped out of the socket in such a way as to be easily reconnectable and reuseable. I like when that happens.
To increase She Ra’s forward slouchability, I heated her up in boiling water to soften the plastic. Then I modded both her under bust joint and her hip sockets with an Xacto knife, gouging out excess plastic to create more room to move. As you can see, I cut a channel in the front of the top of her lower torso, reamed out the bottom of her boobs, and carved out the tops and insides of her thigh sockets. Then I snapped her under bust post back into the socket.
Hey, lookit that! She can now slouch forward significantly from her under bust joint. Plus her enlarged thigh sockets permit her to lean even farther forward. While my mod looks messy, that’s just because of the way that I work. If you go more carefully than I do, you can increase your She Ra’s flexibility with little to no recognizable alteration in her body shape. Go forth and mangle your collectibles! =P