The poem 'The Frog and the Nightingale' by Vikram Seth depicts the story of a boastful frog who takes advantage of a talented nightingale, leading her to train excessively until she ultimately loses her life. The narrative highlights themes of manipulation and the consequences of losing one's individuality for the sake of others' approval. The moral emphasizes the dangers of being gullible and the need for self-awareness in the face of exploitation.