I didn't understand why....(spoilers)
...she ran away looking for the man she was in love with but then when he smiled at her she decides to go back to the quarter.
It's not because he smiles at her. It's slightly better explained in the manga but you have to see his expression. He looks in shock at first like a skeleton in the closet has just been revealed. Then he smiles nervously because he thinks it's just his imagination. So she realises that all his sweet talk really meant nothing.
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