Courtship vs dating wikipedia
There are laws regarding children being involved in sexual contact.
These laws can be enforced based on the age differences between the parties.
Before proposing marriage, you need to earn 10 hearts of friendship with your intended partner, which requires you to give them a bouquet.
“Before you ask someone to marry you, you'll have to date them for a while first (Ask someone to date you with a bouquet from Pierre's).
When you're ready to pop the big question, you'll need to give them a 'Mermaid's Pendant'.
If there comes a day that you want to ask for someone's hand in marriage, you'll need to give them a 'Mermaid's Pendant'. During Winter, it does not rain, so he will not appear unless you use a Rain Totem.
Don't worry, everyone in Pelican Town understands the significance of the amulet. He will not sell the pendant unless your farmhouse has been upgraded and you are at 10 hearts with an eligible villager.