What does Lyle's enjoyment of licking sweat symbolize?

Lyle's enjoyment of licking sweat of the tennis students symbolizes that he likes to feed off the exertion of others. He seems to enjoy seeing the hard work and effort other people put into work. He also appears to enjoy helping the other athletes, since he is a guru. His habit might also symbolize the enjoyment he gets from being around young athletes, meaning that he is feeding off their youth in more ways than one.