Achevements

We are watching

 * Unlock the Illuminati ending (Ending 5).

Uninstall Me

 * For unlocking all achievements

The Fastest in the Wild West

 * Click 276 times for the Panda ending (14th) in under one minute.

Red Baron

 * Complete ending 15 (City Boom!) without missing.

Perfectionist

 * Complete the game without hitting any unnecessary buttons.
 * This achievement is slightly bugged.

Once Again

 * Delete save file with all open endings unlocked.

Just Logo?
The button is in the logo of the game.
 * Press the hidden button in the menu.

Groundhog Day

 * Restart 100 times.

Ergophobia

 * After getting ending 1 (Patience ending), wait 3 minutes before resetting.

Don't be distracted

 * Click 277 times on the counter. (14th ending)

Disobedience

 * Click the button.

Decorate the room

 * Unlock every ending.

Button Maniac

 * Click 1000 buttons.

555-2368
With the black light, shine it above the "Is she here?" wallpaper outline.
 * Who you gonna call?

3X5X6
The puzzle for the cleavage ending.
 * Solve the secret puzzle in under 6 moves (22th ending)