The term 'Sly Quality' can be defined as a type of GUILE, which is a cunning or crafty intelligence. It is often used to describe someone who is able to manipulate others in order to get what they want. This type of behavior is often seen as unethical and can lead to negative consequences. GUILE is often used in a negative context, but it can also be used positively when used in a way that benefits everyone involved.