HC (Hot Cock) is a term used to describe an attractive male. Hot being used to describe the attractiveness of the individual and cock being used to denote the sex of the individual. Because of the crudeness of the the term it is more commonly abbreviated to HC.
"Check out the HC sitting at the table over there"
"Cant wait to get me some HC tonight"
The term has evolved spin-offs since inception and now includes the term HV (Hot Vag)