「Bowing and bending over in lordosis position」with「out-of-reach bodily cavity」「sheath surrounding within attractive over-under orifices in the lordosis servicing position proceptive phase, courting in-your-face female」describes the old Chinese manner of MANAGEMENT, managing a situation: as a preventive countermeasure to mitigate uncontrolled spurting and provide for easier clean-up afterward: polished hollow bamboo shafts were gently and carefully inserted into the rectum in order to remove the fecal matter nearest the anus prior to copulation in that orifice: the MANAGEMENT OF SURROUNDINGS by means of a FECAL COLLECTION SYSTEM. Naturally, the king's imperial court eunuchs and concubines were provided with finely polished jade TUBES, PIPING, a DUCT (see 琯)…don't think so? take a look at some erotic Chinese art.
　A CULVERT is a CHANNEL FOR MANAGING SEWAGE WASTE excrement and/or excessive rainwater to prevent soil erosion. Large sections of bamboo joined and used to channel excrement outside the palace to reduce the stench inside: WASTE MANAGEMENT.
　Clearly,「backside orifices」possess a tubular shape in most cases, and function as the end of a long PIPE known as the alimentary canal, the long internal pathway that provides nourishment to an animal, with the other end being its mouth, generally.「Bamboo and backside orifices」meaning FLUTE, controlled sounds created by controlled air flow through orifices (see 呂), not unlike various toots caused by releasing farts. Lower element is likely「out of reach anus」or,「surround from above with lower level cavities」to denote the source of olfactory unpleasantness requiring a vent for proper management of the environs, i.e., flatulence. Indoor pipes were air vents in China that may have first employed large pieces of bamboo as piping to CONTROL THE FLOW of air into and out of roofed pit holes, primarily to eliminate odors from methane-laden flatulence and decaying meat of varying kinds.
　GOVERNING CONTROL, MANAGEMENT TACTICS, GOVERNMENT ADMINISTRATIVE REGULATIONS were ordered BY LAW and enforced during endemic outbreaks of sexually transmitted diseases in the attempt to stem the tide. Infected people were forced to wear a codpiece and loincloth to prevent contagious dripping in public places, and undergo treatment by reaming with a bougie, again and again until symptoms abated. Official records were maintained of the treatment results to enable tracing of an outbreak or resurgence, and shaman brute squads enforced the laws under government authority, going door to door when the need arose (see: 'magistrate, authority' 尹 and 津).

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: to take care (of); to control; to manage; to be in charge of; to look after; to run; to care about; tube; pipe; (spoken) to; towards
Japanese: pipe, tube, culvert
Unihan extended: pipe, tube, duct; woodwind music
EDRDG: pipe; tube; wind instrument; drunken talk; control; jurisdiction

Used within names (nanori)
すが