In H.H. Munro's (also known as Saki) short story of teenage mischief "The Open Window", the main character is Vera; a fifteen year old young lady who is also the niece of Mrs Stappleton. The latter is the woman whom Mr. Frampton Nuttel comes to visit as a formal guest to be able to spend some time away after having suffered a nervous breakdown.
Vera's characters is well-foreshadowed in the very beginning after he meets Mr. Nuttel. When she welcomes him in, Saki describes the following:
MY aunt will be down presently, Mr. Nuttel," said a very self-possessed young lady of fifteen; "in the meantime you must try and put up with me.
Here we see that Vera is "self-possessed" which means that she has the manners, the attitude, and the persona of someone who is well-under control of herself. This, when compared to the present state of Frampton, serves as an indicator that the two contrast greatly. However, it tells us also that, out of the two, it is Vera who has the potential of controlling the entire situation to her wishes. This is why she subtlety adds that one sentence which foreshadows her:
You must try and put up with me.
From that alone, we can sketch Vera as a cunning, mischievous (she is not necessarily a "bad" kid, just a mischievous, trying, and curious one), and as quite much wiser than we think.
During her story about the open window, which is false and calculated to scare Frampton, Vera shows a myriad of well-planned mannerisms that account for her love of mischief: She dramatizes, elaborates, embellishes, takes away truths, adds lies, and controls her story just for the sake of driving Frampton crazy. She does this for no other reason than to please herself. This helps us sketch Vera further as dramatic, creative, inventive, artistic, and of course, a bit perverse.
After witnessing the arrival of the three - MUCH alive- house men coming from hunting, Frampton has become so enthralled with Vera's story that, when he saw the supposedly dead men arriving back to the manor he blasted off in panic.
Vera does not acknowledge nor makes much of the situation. She simply explained to her aunt how curious Mr. Frampton was in coming and going this way. This seals the deal: Vera is a girl who may have become so bored with life in the country (as many other country Victorian estate young ladies did), that she has excelled at the art of storytelling. We cannot take away the hint that Saki gives us with Vera: She, her wit, her storytelling techniques, and her bit of malice reminds us of another witty, malicious storyteller: Saki, himself!