So open world sandbox game? I was gonna suggest Just cause 3 but there is no "Loving" in that game. Sound more like Grand theft auto 5 i guess, there is hookers, and you basically do way too much with almost no limits. I watch twitch streamers play online with others who just randomly kill each other and team up and do bank heist and other dumb stuff. Retro city rampage was a favorite of mine, it has a free play mode where you basically just do whatever you want in the open world, but is very small world considering the game is about 40MB and looks like a nes graphics, but there is mods i think for custom characters.
What you asking may be a bit of a stretch. Not many games are like you requested, custom character, non mmo. Most games that do have custom characters now and days are encouraged to be MMO, and hardly have Lovers to return to considering is fictional and not the focus of the game. That game would have to combine open world freedom with dating sim and custom character development which has yet to exist all at the same time. Good luck finding that game, but Grand theft auto and Maybe saints row 4 are close to it.
