If a shy person happens to find you attractive, he or she might take your interest in them as being more than just friendly conversation. Make sure you don't give this impression. Some shy people may develop a very long term crush or even fall in love with you and not let you know for months or even years. If you suspect your shy friend might be attracted to you and you do not feel the same way about them, try to make it as clear as possible early on. You will save them a lot of pain.