Though even Yoshika is snarking with her talisman changing letters into "boomerang".
Edit: Quoting myself from a different post:
NNescio said in post #4589585: (...) "Yang Xiaogui" is considered black magic heretic stuff in Taoism (and Buddhism) and in general Chinese culture, for those aware of the term (it is obscure). It is sometimes ascribed to the Maoshan sect of Taoism, but the Maoshan sect gets hit with all sorts of black magic allegations in fiction and legends anyway, and the actual Maoshan sect would probably strongly proscribe against such practices.
In xianxia fiction (Chinese Hermit Sword & Sorcery) "Yang Xiaogui" is usually considered black magic necromancy, and used as part of a shorthand for "this sect or person is spooky spooky EVIL, mm'kay?" Like how necromancy is generally used in Western works. (Just creating and manipulating jiangshi isn't though, despite being technically necromancy by Western fiction standards. Because corpse-transporting was part of the real-life duties of Taoist priests. Though killing someone just to raise them as a jiangshi slave is a different story.)
Trying to figure out the origin of this practice somewhat stumped me though, but a lot of Chinese language sources mentions that is derived from the Thai Kuman Thong practice, or similar animism practices in other parts of Indochina. In particular, "Kuman Thong" effigies still get smuggled to Taiwan and Hong Kong and Mainland China (rich businessmen and celebrities love them as some kind of good luck charm) where they will sometimes get described as "yang xiaogui". There is some kind of... odd distinction where "kuman thong" is used for supposedly "legit" totems (given up willingly and blessed by a Thai Buddhist monk), while "yang xiaogui" is used for the less "legit" ones, but personally I think it's just a load of self-delusion.
Kuman Thong is still considered an acceptable cultural/religious practice (of sorts) in Thailand. Even Buddhist monks engage in making them, though occasionally one or two will get defrocked and expelled for doing so. There's a lot of... weird technicalities involved... on whether it counts as heresy or not depending on what body parts are used and how they are acquired.
Though even Yoshika is snarking with her talisman changing letters into "boomerang".
Edit: Quoting myself from a different post:
Wow , Thks ,i guess ??? Till thks for information
Modifying your own children into a shield for curses!?
That's horrible!A foul magic art that exploits children as reagents for your own purposes...
How... How terrifying!!