This line suggests that Aunt Agatha is in a state of shock or distress. The details in the line imply the following:
- "Bolt upright" indicates that Agatha is sitting very straight and rigid, which suggests tension or anxiety. People normally don't sit perfectly upright unless they are disturbed in some way.
- "Staring into space" implies that Agatha is so lost in thought that she is unaware of her surroundings. Her gaze is unfocused. This detached expression is often associated with trauma, worry, or contemplating something deeply troubling.
- The fact that she is sitting still and staring blankly, rather than engaged in any activity, implies that something is weighing heavily on her mind. She appears paralyzed by her thoughts.
- The visual image of Agatha sitting upright and staring evokes a sense of shock and disorientation. The line paints a picture of someone who has just received very distressing news or experienced a traumatic event.
In summary, the line implies that Aunt Agatha is in a state of distress, shock, or trauma, utterly preoccupied by whatever is on her mind to the point that she is oblivious to her surroundings. Her posture and expression signal anxiety, uncertainty, and intense contemplation. The line suggests something has happened to profoundly shake or trouble Agatha.