Here is the full list of all 28 Strawberry Vinegar achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Ate candyfloss.
Ate shaved ice.
Became Licia's best friend.
Ordered omelette rice.
Ate pickled plums.
Made Licia some chicken cutlet sandwiches.
Said a sad farewell.
Made Licia strawberry risotto.
Forgot everything.
Bought Licia a crêpe.
Bought Licia an onigiri.
Embarassed a fearsome demon.
Watched a fearsome(?) demon eat a corncob.
Gave Licia a chestnut pudding.
Encountered a fearsome demon.
Became Licia's (long-suffering) girlfriend.
Savored a strawberry sundae.
Ordered a hamburger steak.
Baked Licia a cake.
Made Licia rice porridge.
Made Licia pancakes.
Ate chichi dango.
Ate takoyaki.
Baked apple rose tarts.
Ate tempura shrimp - plus sides!
Ate natto (begrudingly).
Baked cookies.
Ate miso soup.