You know you’ve read a good book when you turn the last page and feel a little as if you have lost a friend.

The line captures a common readerly experience: truly immersive books create relationships—parasocial but emotionally real—with characters, narrators, or even the authorial voice. Finishing such a book can feel like a small bereavement because the daily companionship of that imagined world ends abruptly. The quote also implies a standard for literary quality rooted in affect and attachment rather than plot mechanics or stylistic virtuosity: a “good book” is one that makes the reader care enough to miss it. In that sense, it celebrates reading as a form of friendship—intimate, sustaining, and capable of leaving a lingering absence.