Here is the full list of all 31 Meta Meet Cute!!! achievements.
Complete Rumi’s route
Complete Mei’s route
Complete Meguri’s route
Get turned down by Mina
Press the button that must never be pressed!
Try becoming a heroine!
It’s the string play spider baby!
Experience the end
Spend your days by the pond
Become a lethal weapon
Complete your duty protecting the blackboard
Love your desk
Hawk
Help out writing a book
Spread the word about Hanako
Make the princess fall for you
Become the strongest duelist
Become Tomoko’s friend
Bond with your pencil
Just keep walking east
Don’t get reborn in another world
Go to Kyoto
Make a promise with Rumi
Finish all endings (No DLC)
Spend your future with everyone
Roleplay
Become the very best science club
Play baseball
Escape the cave
Finish all endings
Spend your future with everyone+