Its main goal is simplicity. I want it to be really easy to read and write with useful features out of the box (relationships decorators, timestampable models, soft deletes, protection against mass assigment, model events, caching).
I started it as a personal need for simplicity when defining my models which is one of the things I like about Ruby On Rails.
It is inspired by the database part of the Laravel PHP framework, but modified to be more pythonic.