WWYD?
The Demon Lord of MGE has found a way to our unsuspecting world, Earth (21st century). She wants to takeover the Earth, and do what she's already doing in her world to Earth. The Demon Lord wants to carefully plan her invasion first in a few years or a decade in advance before starting it. The invasion would start small, then it would grow over time. The Demon Lord does not want any killings during the invasion.
You (a Mamono, or an Incubus) are tasked by the Demon Lord to help plan and lead the invasion. So, you traveled to Earth in human disguise for a few years to scout and learned everything about it. After traveling to Earth for a few years and learning everything about it, you come back to the Demon Lord with an Invasion plan of the Earth. Which country, or which part of the Earth would you think it's best to takeover first? How would the invasion go from there?