In the first Harvest Moon, you initiate marriage by offering them a feather.
In JRPG Great Greed, you just pick your partner as your end-game reward as the several princesses you've met congregate to the victory room.
It can even be with NPCs in the room! Though no "romance mechanics" are included, it's similar to Fallout's marriage system. (Though I hear in later games you can win over NPCs via quests to open up marriage.)
For something like Last Of Us, mobile game Rebuild 3: Gangs of Deadville let's you play matchmaker. You can cozy up fellow survivors when you assign them on daily duties together. Be it fighting zombies, pillaging roses, or strolling under the moonlight patrol. Dating, marriage, even parenting can happen in this strategy game.
In Terranigma, you can actually help two penguins fall in love (by fetch-questing flowers).
In romance simulator True Love '95, you can skip wooing the typical choices and just live your own life, praying, and taking care of an abandoned cat.
After enough care will reveal she is an angel and falls in love with you.GB classic Survival Kids, later known as Into the Blue, has a story branch where you
can find another castaway, keep them alive, even fall in love with them.Mobile game Azur Lane centers around organizing anthormorphed ships into combat with combat. After being ordered through enough victories (maybe taking breaks in a fully furnished commissary), the ships trust and eventually fall in love with you Admiral.
Conquest of the Crystal Palace had shop-keeper Kim. If you amassed enough coin (likely in a 2nd or 3rd cycle) you could clear her shelves repeatedly. She will initially compliment you and eventually swoon (though all she does is give you the same discount each time).
Franchise Princess Maker actually has you play as the damsel ...'s dad. Depending on where you send your girl off to work (or play or adventure), she can meet various paramours who do everything from partner up to compete to outright bribery to win her hand.
-=PakoPako=- (Proud member of board 917023!)
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