Do I have to return to the U.S once my 90 days allowed in Germany are expired?

Question: I am living with my fiance in Germany. He is in the military. We are not married yet, therefore we are not sponsored through the military for

Source: http://www.us-passport-service-guide.com/do-i-have-to-return-to-the-us-once-my-90-days-allowed-in-germany-are-expired.html

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