Here is the full list of all 33 Giraffe and Annika achievements.
Unlocked all achievements
Beat the game within 4.5 hours
Ate 50 foods
Cleared all rhythm games on all difficulties at A rank or higher
Cleared every rhythm game with no misses
Obtained all bonus drawings from rhythm games
Cleared dungeon 5
See every conversation with Mrs. Save
Cleared every rhythm game at normal or higher
Cleared all rhythm games on hard mode
Cleared every hard rhythm game on S rank
Obtained 3 bonus drawings from rhythm games
Collected all meowsterpieces
Hit every drum
Stuck your face into every photo stand-in
Cleared dungeon 4
Delivered something Giraffe forgot
Collected every mysterious paper scrap
Collected 24 meowsterpieces
Changed into the swimsuit
Collected 18 meowsterpieces
Cleared the Fire Dungeon
Collected 12 meowsterpieces
Took 50 or more photos
Saw the special idle animation
Cleared the Ocean Dungeon
Collected 6 meowsterpieces
Cleared the forest Dungeon
Got 'Great Fortune' result on my fortune
Obtained the bag
Received a Christmas gift
Obtained the key to Lisa's house
Went into the bathroom 5 times