cohabitancy
/kɒh.bɪˈtæn.si/Definitions
1. noun
the state of living together with someone as partners, usually in a romantic relationship, without being married
“The increasing number of couples choosing cohabitancy over marriage has led to a shift in societal norms.”
2. noun
a shared living space or home
“Their cohabitancy was a cozy apartment in the heart of the city.”