Some characters are best in small doses, but can quickly wear out their welcome if promoted to regular status. I suspect a full-time Sue might start to grate.
Time travel plays merry havoc with causality. Her interaction with him occurred before her trip to drama camp from his point of view, even if it happened later from her point of view.
Some characters are best in small doses, but can quickly wear out their welcome if promoted to regular status. I suspect a full-time Sue might start to grate.