"Books have their own destiny" - said the ancients. The same applies, of course, to words. Some of them are enriched with new meanings, others are poorer and leave the language. Maybe the word "demon" would have left Russian speech with the loss of mythological and religious ideas, if not for the poem that preserved it. Mysterious and exotic for Russian hearing, this name enters our consciousness along with Lermontov's poems and remains in it forever. Carrying all the wealth, all the immense meaning of a work of art, it is perceived through the music of lines and stanzas, through their bewitching sound.