Term describing the phenomenon of when there is a chill vibe between 2 (or more) people who engage in intercourse. HOWEVER there is no friendship involved, just a mutually positive association between sexual partners. Fucking is not the sole aspect of all interactions and some other benefit comes from timespent together (i.e. conversation, life perspectives etc.).
"No dude I'm not trying to be friends with him! We are just chill fucking..."