Here is the full list of all 20 Kathy Rain achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Felt no apparent need to let Lenny down gently
Made your best efforts to miss the funeral
Finished the game
Finished day four
Finished day three
Really had it out for Goober
Wanted to engage in a good 'ol book burning
Totally mesmerized by Goober's monologues
Amplified Goober's lung cancer
Finished day two
Learned a cold hard truth about your face
Engaged in flirtatious behavior on the computer
Barely resisted the urge to barbeque a bear
Finished day one
Tortured an imprisoned bum
Became a huge fan of those sweet, addictive, not to mention cancer-inducing sticks of tobacco
Lost track of time on the road
Rediscovered yourself as a creature of the night
Felt like literally taking the wheelchair for a spin
Reunited with a furry friend