"Afternoon delight" is a phrase that is often used to describe spending intimate or romantic time together during the daytime, usually in the afternoon. Full definition
Trying new things with your partner bonds you in a new way — especially when your activities are adrenaline boosters like watching a scary movie, taking a risk of some kind (for example, cutting out early from work for a little afternoon delight?) (mindbodygreen.com)
Oh, you want to know where I had an intimate sexual encounter and if it was a session of afternoon delight or a romp in the wee hours of the morning? (babygaga.com)