Definition
A person someone has sex with, not in pursuit of a serious relationship, but rather to engage in casual sexual encounters.
性伴（非專注感情關係）
He treated her as a notch on his bedpost, not as someone he wanted a meaningful relationship with.
他把她當成床柱上的刻痕，而不是他想要認真交往的人。
She didn’t want to be just another notch on his bedpost.
她不想只是他床柱上的另一個刻痕。
She ended the relationship after realizing she was just a notch on his bedpost.
她在意識到自己只是他床柱上的一個刻痕後結束了這段關係。