Emphasis upon plugging the orifices of「one's own offspring」with「erection screwing」as TOXIC activity causing brain mush, mental retardation, and birth defects (seeds and beans are euphemisms for semen and clitorises, respectively):
　「Take the results of a study of Czechoslovakian children whose fathers were first degree relatives. Fewer than half of the children who were the product of incestuous unions were completely healthy. Forty-two percent of them were born with severe birth defects or suffered early death and another 11 percent were mildly mentally impaired. This study is particularly instructive as it included a unique control group — the offspring of the same mothers but whose fathers were not the mothers' relatives. When the same women were impregnated by a non-relative, only 7 percent of their children were born with a birth defect…」
　　[　https://www.psychologytoday.com/intl/blog/animals-and-us/201210/the-problem-incest 2023-05-18　]　
　CASTOR beans or seeds are the most toxic plant substances known to science, one that will cause brain seizures and a sitting position for a long time:「Although the lethal dose in adults is considered to be four to eight seeds, reports of actual poisoning are relatively rare. According to the 2007 edition of the Guinness Book of World Records, this plant is the most poisonous in the world. Despite this, suicides involving ingestion of castor beans are unheard of in countries like India where castor grows abundantly on the roadsides, which may be attributed to the rather painful and unpleasant symptoms of overdosing on ricin, which can include nausea, diarrhea, tachycardia, hypotension and seizures persisting for up to a week. …If ingested, symptoms may be delayed by up to 36 hours but commonly begin within 2–4 hours. These include a burning sensation in mouth and throat, abdominal pain, purging and bloody diarrhoea. Within several days there is severe dehydration, a drop in blood pressure and a decrease in urine. Unless treated, death can be expected to occur within 3–5 days…」
　　[　https://en.wikipedia.org/wiki/Castor_oil_plant 2013-04-15　]　
　Analogous to having thoughts of「shafting youthful harem flowers on the brain, soft spots in skull, concubine feet covered by slimy mucus」and so on.
　Oil from castor beans can be used as a laxative with fairly immediate and dramatic results depending upon the quantity administered:「As a means of punishment or torture, force-feeding castor oil still lives on in animated cartoons such as Tom and Jerry. …In Fascist Italy under the regime of Benito Mussolini, castor oil was one of the tools of the Blackshirts. Political dissidents were force-fed large quantities of castor oil by Fascist squads. …Victims of this treatment did sometimes die, as the dehydrating effects of the oil-induced diarrhea often complicated the recovery from the nightstick beating they also received along with the castor oil. However, even those victims who survived had to bear the humiliation of the laxative effects resulting from excessive consumption of the oil. It is said Mussolini's power was backed by 'the bludgeon and castor oil.' In lesser quantities, castor oil was also used as an instrument of intimidation, for example, to discourage civilians or soldiers who would call in sick either in the factory or in the military. Since its healing properties were widely exaggerated, abuse could be easily masked under pretense of a doctor's prescription. …It was also often used as both a punishment and torture by the Spanish Nationalists, led by Francisco Franco, as they purged Spain of those who supported the democratic, left-wing Republic during the Spanish Civil War.」
　　[　https://en.wikipedia.org/wiki/Castor_oil 2013-10-14　]　

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: the castor-oil plant
Unihan extended: castor-oil plant, Ricinus commumis
EDRDG: castor-oil plant