The essay revolves around Nawab Sahib's eccentric behavior of meticulously preparing a cucumber with salt and pepper, smelling it to enjoy its fragrance, and then throwing it out the window without eating it. This entire act is a display of his 'सनक' (eccentricity/whim) under the guise of 'खानदानी तहजीब' (family refinement). The context itself refers to this behavior as सनक in question 6. Therefore, 'खीरे की सनक' captures the central theme perfectly. Other acceptable alternatives could be 'नवाब की सनक', 'खानदानी तहजीब', or 'कल्पना की तृप्ति'.