@murky This prompt doesn't invoke the pose at all:

masterpiece, best quality, extremely beautiful and delicate, extremely detailed, intricate detail, vivid colors, colorful, bloom, 1girl, legsupms,

Here, it starts to surface, but with anatomical glitches (notice how the tags removed have nothing to do with poses):

masterpiece, best quality, extremely beautiful and delicate, extremely detailed, intricate detail, 1girl, legsupms,

Here, it gets closer, but still with noticeable glitches or nothing but the legs:

masterpiece, best quality, 1girl, legsupms,

Negative prompt so far:

NG_DeepNegative_V1_75T, Unspeakable-Horrors-64v, bad_prompt_version2, sketch by bad-artist, EasyNegative, super_uglyv3, (((lowres))), bad anatomy, bad hands, cropped, ((head out of frame)), (worst quality, low quality:1.4), (((normal quality, what, parody, surreal, pablo picasso))), jpeg artifacts, signature, watermark, username, blurry, (((fat, fat mons, obese, ugly, uglier, ugliest, bad artist, flat chest, flat ass, skinny, bad perspective, sagging breasts, pubic hair, flat color, flat shading, pale color, washed color, loli, child)))

Reducing it to the following was what let me sometimes get the desired result:

bad_prompt_version2, (worst quality, low quality:1.4)

But the resulting image quality dropped drastically.

Sampler is Euler a, 20 steps on all test cases, resolution is 360x360 with hires.fix set up to 2x.

@murky Putting legsupms as the first tag does help a bit, but it still gets overwhelmed very easily by other tags that are not even pose-related.

simply reinforcing the prompt like putting : (legsupsexms:2)
Did the joke for me, I had the pose I want at least once every 3 times.