To call someone a Sleezy Bear is to point out their profound involvement him/herself has in the most dirty and trashy sexual activities and how they tend to brag about it, A Sleezy Bear sometimes spits and sleeps in its own cloths. A Sleezy Bear also very rarely tips his/her waiter.
This insult also hints at the fact the person may or may not be of the bear species.
Person 1: "Did you hear about that guy?"
Person 2: "Yeah he's such a Sleezy Bear, he never tips"
Person 1: "I heard he gets up to the weirdest disgusting sexual activities with peoples parents"
... Meanwhile in another place ...
Sleezy Bear: "This one time, I slept with with my clothes on after sex, I then decided to hibernate.."
The year after graduating high school during which one sleeps for an entire year instead of going to college. After one wakes up, college begins. A sleepyear is used as a way to fully regain one's energy after the exhausting years of high school, so as to be fully awake and ready to get down to business in college.