Harvest Moon/Tear Jerker

"Your Character:"
 * The very end of Harvest Moon: A Wonderful Life. No, not, or even The very last line your character speaks in the game. When your wife observes how you've both gotten old, and aren't the glamorous young things you used to be.

"Muffy:"
 * Previous to that; given what a Sugar Bowl the series usually is,  death in Harvest Moon 64 doubles as this and the closest thing the series has to a Wham! Episode. Elli's reaction just drives the trope home.
 * What about death? You never expect it, plus most people don't become friends with her in time.
 * The multiple Fridge Horror's that mixes when you notices about Karen's Bottle Fairy habits, her Broken Bird status, and her fathers implied alcoholic nature mixed with his easily angered temperament in Harvest Moon 64. It's even implied that he is abusive toward Karen and his wife.
 * Screwing up anyone's love life. For example: making a character leave the game (like Kai or Cliff), turning down a character, choosing a bad option in a love event, or (sometimes) courting a character. It's even worse in the Wonderful Life series, especially in the first game. If you court a character and marry another, they'll go to your house crying and basically give you a "You Suck" speech.
 * Out of all the "betrayed" scenes in A Wonderful Life, the saddest has got to be Muffy's. Let's just say that if you don't feel bad about getting Muffy to four hearts and then proposing to someone else, then you have no soul:

"Gill:"
 * I remember when during my first gameplay I courted Celia and married her. I had also made friends with Nami, and during the cutscene with the MC and Celia telling everyone in town the 'good' news, Nami walked away with a pained expression. I had never felt so guilty.
 * Animal Parade: What Gill says in the Japanese version of the game if you tell him you don't like him back when he confesses to you.