The act of one going up to a girl and grabbing her boob and when she goes to slap you, you block it with your hand appearing as if she gave you a high five.
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!