About "Crushes"
Puppy love is an informal term for feelings of love, particularly between young people during adolescence, so-called for its resemblance to the adoring, worshipful affection that may be felt by a puppy.The term is often used in a derogatory fashion, describing emotions which are shallow and transient in comparison to other forms of love such as romantic love.
Another use of the term (also commonly described as a "crush"), can be used to describe the love or lust of a child or adolescent for an adult. For example, a student being attracted to his or her teacher could be considered puppy love. In this case, the term relates an infatuation which is frequently not reciprocated. The term may meet with resistance from some people as patronizing and belittling of genuine emotion.
Source: Wikipedia