So basically the protagonist was part of the hero's party, not the hero himself, after the demon lord was defeated everyone went their separate ways, the hero married the purple-ish haired samurai girl and the other 3 girls also married other people, the protagonist couldn't develop further relationships with the other girls bc he discovered the queen (dlc girl) cheating on the king, which ended up with him being banned from the kingdom and not seeing anyone for years.
Time passes and demon lord revives, everyone but the hero (he ded) reunites once again to battle him but now the mc can empower the girls but with a cost and blah blah blah.
Each girl has a pure love route and a lust route (the latter one being the one where sharing/nts/whatever stuff happens), after the second event or so of a route it will be locked, so you can avoid any cuck shit if you just do the pure love route stuff.