Цветочное алиби

What do you think of a man who regularly visits a flower shop, buys three white irises, and then, after walking a few blocks, puts them in a trash can? Either he performs some kind of romantic ritual, or he goes crazy, or he is in love with one of the shop assistants, or ... No one guessed the existence of the fourth "either" - neither the naive flower girls, nor the sophisticated Marisha, who, meanwhile, unraveled the case of mysterious murder, where the buyer of irises passed as one of the suspects. The fourth "either" was just his alibi ...