Responses

That's a variation, too - but as I saw it, he went for the place where the leg joins the lower body, and even if the direction might be misleading (is there anything NOT misleading in yaoi?) - there's a proper therapeutical grip to relocate/adjust the hip/lower back ^^
Though a "proper" bonesetter would tell you beforehand what he's about to do (to avoid ppl tensing up, or slapping him - the only instance they don't warn you before hand is when they're trying to fix your neck ^^)
What sort of chiropractor grabs someone bu the crotch and thinks it will solve something (especially before trying to do anything else??? - ah Yaoi - it often makes no sense.)