Summ boi also known as some boy is a person who has excellent banter or humour. Or in certain circumstances can be used to describe someone who is a great guy.
"What have you got me there Barry?", "Well Josh, I've got you some Barry's Red Cola.", "You are summ boi Barry, you are summ boi."
by geoff shreves June 03, 2016
buy the domain for your cat site