When it is heavily implied (but not directly shown) that someone has just had sex, usually by context clues such as stained panties, sweaty clothes, a disheveled appearance, sunken cheeks, unconvincingly acting like nothing happened, inconspicuous cum or used condoms, stray pubic hairs, etc.
See after sex for when it's unambiguously shown that the character has just had sex, rather than indirectly hinted at or implied. After sex usually takes place still in bed, while implied after sex does not.
