live-in lover/boyfriend etcLIVE WITH somebodysomeone who lives with their sexual partner but is not married to them （未婚）同居的情人/男朋友等live-in lover/boyfriend etc• Two divorces, a long string of live-in boyfriends.• She took no new live-in lover, and as far as she was aware, neither did Charles.• She met her live-in boyfriend on-line.• She had a live-in boyfriend to whom she devoted most of her time and energy.
→ live-in lover/boyfriend etc at live-in(1)