In the distant future, Princess Twilight ushers ponykind into the stars, building a massive colony ship to bridge the vast spaces between solar systems and spread friendship throughout the galaxy. The ship is powered by her gigantic, milky tits.

If you've ever wanted the joys and perils of an interstellar voyage to go with your fapping fuel, or vice versa, this is the story for you. Contains unreasonably large breasts in greater than standard numbers, among other sexy things.

The coverart is my extremely quick-and-dirty edit of a work by whisperingfornothing on Derpi.