Here is the full list of all 33 Giraffe and Annika achievements.
Unlocked all achievements
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 every hard rhythm game on S rank
Cleared all rhythm games on hard mode
Obtained 3 bonus drawings from rhythm games
Received a Christmas gift
Beat the game within 4.5 hours
Cleared dungeon 5
See every conversation with Mrs. Save
Cleared every rhythm game at normal or higher
Collected all meowsterpieces
Hit every drum
Stuck your face into every photo stand-in
Cleared dungeon 4
Took 50 or more photos
Collected 24 meowsterpieces
Delivered something Giraffe forgot
Changed into the swimsuit
Collected every mysterious paper scrap
Ate 50 foods
Went into the bathroom 5 times
Collected 18 meowsterpieces
Cleared the Fire Dungeon
Collected 12 meowsterpieces
Got 'Great Fortune' result on my fortune
Saw the special idle animation
Cleared the Ocean Dungeon
Collected 6 meowsterpieces
Cleared the forest Dungeon
Obtained the bag
Obtained the key to Lisa's house