The Kickstarter page states that every person in Citizens of Earth will either be "a recruitable character or an enemy," meaning you'll be amassing an extensive party as you progress through the game. Since these are everyday people, however, they'll be managing their day jobs when they're not helping you in battle. Leveling them up in battle will improve their aptitude towards their work, allowing players to "develop the world at large" by leveling up characters instead of just bumping up stats.
Citizens of Earth's "citizens are optional to recruit and most areas are optional to explore," meaning there should be something to love for both hardcore adventurers and those hoping for a streamlined romp through a bunch of jokes.
Should the campaign's goal of $100,000 (Canadian) be met, Citizens of Earth will launch on the PC, Mac and Linux. Stretch goals include ports to the Wii U, 3DS, PS4 and Vita as well as a slew of gameplay improvements like additional stories and multiplayer battles.