A girl who acts as a Mac Guffin, or otherwise motivates the whole plot.
This will be a supertrope and/or index.It really seems like every adventure is motivated by a girl. Whether it's to save her, protect her, follow her or get her to fall in love with you, girls seem to be the chief reason any hero does anything. Hence, the Plot Girl. The Plot Girl is the female character who the plot revolves around. No, not The Hero, he's the one who gets to run around after her, the Plot Girl is his motivation, one way or another. She might be a co-protagonist to The Hero, but essentially, she is his Call to Adventure.
The Plot Girl has a number of notable subtropes. Keep in mind that while not all of these subtropes require the character to be female, to qualify for this trope, one must be:
Related Tropes, which may also act as Plot Girls or are often associated with Plot Girls:
Examples not belonging to subtropes:(Should we have this section?) Comics