sûn-chhân-chúi巡田水

to inspect irrigation water and facilities

to inspect irrigation water and facilities in the fields; to get laid, to bang (specifically referring to a man having sex with a woman)

slangeuphemistic

English Wiktionary, “巡田水” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E5%B7%A1%E7%94%B0%E6%B0%B4 · confidence: Medium (Wiktionary)