With the narrative related through the mind of a bright, creative child such as Nicholas, there is an imaginative and exaggerated perspective of the antagonist, the self-appointed aunt, that is delightfully satiric of the rigidity of those without imagination.
In rebellion against the trivial, unimaginative, and rigidly authoritative aunt, Nicholas places a frog in his bowl, then pretends that he does not know how it got there because he is aware that in her doctrinal arrogance she will not even bother looking into the bowl, but, instead, declare that there is no such frog. When the aunt does see the frog, then she forbids Nicholas from joining the other children on a trip to the beach. However, the aunt's character flaws are not unnoticed:
The sin of taking a frog...and putting it into a bowl of wholesome bread-and-milk was enlarged on at great length, but the fact that stood out clearest... to the mind of Nicholas, was that the older, wiser, and better people had been proved to be profoundly in error in matters about which they had expressed the utmost assurance.
Further in the narrative, Saki's cynical humor is so well illustrated when the aunt calls to him from the forbidden gooseberry garden and Nicholas cleverly reverses the impositions put upon him by reversing the penalties of them upon her. For instance, when she falls into the rain tank and cannot get out on her own, he forces her to remain there because he has been forbidden to enter this garden by her own dictates of earlier that day. Cleverly, he pretends that he thinks she is the tempting voice of the devil and acts the obedient child. Ingeniously, he then tricks her into saying he may have strawberry jam when previously she has said there was none. Nicholas tells her that he now knows for certain that she is the "Evil One":
...when we asked aunt for strawberry jam yesterday she said there wasn't any. I know there are four jars of it in the store cupboard, because I looked, and of course you know it's there, but she doesn't, because she said there wasn't any.
That evening after the other children have returned from an outing that has been a dismal failure because the rigid aunt failed consider the tides and the discomfort of Bobby's boots,
The aunt maintained the frozen muteness of one who has suffered undignified and unmerited detention in a rain-water tank for thirty-five minutes
The imaginative Nicholas is also silent, but his reticence is a rapture of delight as he imagines now that the hunter may just be able to escape with his hounds as the wolves are occupied with devouring the stag.