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.
Get an 'A' rank in all Mode 2 levels.
Completed the final level.
Completed the fourth level.
Use a frag grenade to end your tea party.
Use the dynamite.
Why would you shoot ted?! He's your best and only friend!
Completed the third level.
Activate the monolith.
Witness the potato box flying through space-time.
Completed the second level.
Witness the Red Baron.
Activate the aviators.
Witness the zeppelin.
Activate the snake.
Completed the first level.
You really aught to do something about that stabbing habit.
Make a tea within a tea, or something.
Activate the sunglasses.
Activate the top hat.
Activate the turnip.
Activate the fish!
Activate the calm book.
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.
Let the chi flow through the spasticity of your hand.
This hand ain't goin' nowhere.