In "Sputnik Sweetheart," Haruki Murakami reflects on the deep connection between the protagonist and the world of books. The character finds that literature offers a vivid, immersive experience that reality cannot match, revealing unseen realms and emotions. This contrast highlights the vibrancy of imagination compared to everyday life.

Additionally, the protagonist's relationships are largely unfulfilling, as they struggle to connect with peers on a meaningful level. While there are a few friends at school, the character feels a profound loneliness, turning instead to books and music as their true companions in navigating life and expressing feelings that remain unshared with others.