The phrase "flies the coop" is typically used to describe someone leaving or escaping from a place or situation. The antonyms for this phrase could be "settles in," "stays put," or "remains." These terms indicate the opposite of leaving a place or situation, suggesting that someone is content with where they are and has no desire to leave or escape. Alternatively, antonyms could include "returns," "reenters," or "rejoins" - all of which suggest that someone is going back to a previous place or situation rather than leaving it. In any case, the antonyms for "flies the coop" involve staying or returning rather than leaving.