Why Mori Girl?
Mori Girl is another style that started in the streets of Japan. When translated, mori girl means forest girl and that is where the aesthetic comes from. The idea is that a girl wandered into a magical forest, got lost, and then came out a few hundred years later. The style is loose and flowing with lots of earthy inspiration from the forest itself. Big ruffles, cozy scarves, fake fur, knitted and crocheted items, vintage items, and a loose comfy fit all fit into the style.
I find this style very easy to blend with other styles such as Lolita. I think this style is very customizable and easy to make your own. A lot of making this style work is inspiration of your own and letting yourself play with the style instead of learning specific style rules.
For those of you who want a starting point, Moss Garden has a good amount of inspiration. Mori girl "guidelines" can also be found here to get your own ideas flowing.