Once upon a time there was a boy who loved a girl, and her laughter was a question he wanted to spend his whole life answering.

The sentence frames love as an ongoing act of attention and interpretation rather than a problem to solve. The girl’s laughter becomes a “question”—something living, changeable, and inexhaustible—while the boy’s desire is to devote a lifetime to “answering” it, suggesting commitment expressed through curiosity and care. The fairy-tale opening (“Once upon a time”) both romanticizes the scene and hints at narrative distance: love is remembered and retold as story. The line’s emotional force lies in turning a fleeting sound into a lifelong vocation, implying that intimacy is sustained by continually trying to understand another person’s joy.