When someone you have a crush on sends you random pictures, it can be a sign that they are interested in you and want to keep the conversation going. They may be trying to flirt with you or simply share parts of their life that they think you'll enjoy seeing. The content of the pictures can provide some insight - if they're mostly selfies or pictures of themselves, it's often a sign of attraction and an attempt to get your attention. But if the pictures are of random objects, places, or things they've encountered, it may just be their way of keeping the interaction going and sharing their interests with you. Ultimately, it suggests they value your connection and want to maintain a sense of playfulness and familiarity in your interactions.