In literature, keen is employed to evoke a sense of acute sharpness—whether of the environment, the senses, or the mind. It often describes the biting, crisp quality of weather or air, as in texts where cold winds and frost are characterized as keen ([1], [2], [3]). At the same time, keen is used metaphorically to depict mental acuity and perceptiveness, emphasizing a character’s sharp intellect or sensitive observation ([4], [5], [6]). Moreover, the term extends to describe decisive qualities in actions or objects, be it the keen point of an arrow or sword, or the intense and sometimes painful emotional experience ([7], [8], [9]).