Heaven is a vast structure. It spans through time and light. It's too much space for the Greater Angels. Not many of them really like the place; they'd rather spend their time playing in the Lower Worlds. It's also too much space for the Lesser Angels (But they lack the power to leave).
To entertain themselves, the Lesser angels built their own worlds within the walls of Heaven.
Paradise was originally one of Heaven's many neglected courtyards. It was just a little bit larger than the other courtyards (but relative to Heaven and the Lower Worlds, it was tiny), and a perfect blank canvas for the Lesser Angels who had found it. The angels envisioned a garden, a place that they could endlessly maintain and care for. They populated Paradise with flora and fauna, which all lived together in harmony. But the peace of Paradise was soon to be disturbed.
A monster. The Lesser Angels didn't know where it came from. They had simply found it, mindlessly tearing apart a carcass. It recklessly uprooted plants and hunted down all the animals it could. The thing had nearly destroyed Paradise's garden.
Perhaps the Lesser Angels should have gotten rid of the pest - That would've been the easiest way to restore the peace.