Yukkuri eating other yukkuri. Usually done by shitheads to "un-easy" yukkuris. This includes when a yukkuri is directly eating another yukkuri, and when doing so in the form of a food made out of yukkuri. Some canons have the yukkuri become addicted to other yukkuri on the first taste.
Yukkuris view eating other yukkuris as uneasy and disgusting. As such a common abuse is tricking a yukkuri to eat a fellow yukkuri (often a family member), usually by removing the "food"'s accessory and either killing them or sealing their mouth shut. This works because in some canons a yukkuri without an accessory aren't viewed as a yukkuri by other yukkuri. As yukkuris are made of bean paste, a yukkuri will usually enjoy the taste of another yukkuri and will happily eat them until the human reveals that they've been eating another yukkuri. The realization will often cause them to puke.
A more direct form of abuse can be done simply by forcing the yukkuri to eat another yukkuri (again, usually a family member) without their consent. In this case the yukkuri will get confused; on one hand cannibalism is uneasy but on the other hand they are disgusted at themselves for enjoying the taste of another yukkuri.