While it was previously established that Lev is a virgin, in this exchange the novel establishes that his crush on Vera is a childish thing easily left behind, and foreshadows that he's likely to meet a woman he truly likes. And according to Kolya, his true interest in this woman will be obvious when he takes note of her eye color. Finally, though, their agreement that neither of them has a chance with the colonel’s daughter further marks how within the Soviet Union there are still class divisions that can’t be breached.