Here is the full list of all 28 Tea Party Simulator 2015 achievements.
Get an 'S' rank in every level, in both Mode 1 and Mode 2.
Get an 'A' rank in all Mode 1 levels.
Make a tea within a tea, or something.
Get an 'A' rank in all Mode 2 levels.
Completed the final level.
Completed the fourth level.
Why would you shoot ted?! He's your best and only friend!
Use a frag grenade to end your tea party.
Use the dynamite.
Completed the third level.
Witness the potato box flying through space-time.
Activate the monolith.
Let the chi flow through the spasticity of your hand.
This hand ain't goin' nowhere.
Completed the second level.
Activate the aviators.
Activate the snake.
Witness the zeppelin.
Witness the Red Baron.
Completed the first level.
Activate the calm book.
You really aught to do something about that stabbing habit.
Activate the fish!
Activate the turnip.
Activate the sunglasses.
Yes, well ... I'd call you a buffoon too if you poured hot water on me. Indeed!
Flip the bird, if the bird were a fancy bird.
Activate the top hat.