Shortened version of "para que sepas", which means "so that you know" in English. May also be heard as "pa que sepa" in places like the Dominican Republic where "s" isn't really pronounced.
Loose English slang translations could include "for your information" or "you know it!"
Example: I rep Puerto Rico all day, pa' que sepas!
I rep Puerto Rico all day, so that you know (/for your information/you know it)!
Fogey/fogy /fougi/ sl. (early 18C+, orig. Scot) old-fashioned, stuck-in-the mud.
Person with old fashioned ideas which he is unwilling to change: Come to the disco and stop being such an old fogey!
You think me an old fogeyand an old tory, his thoughtful voice said. I saw three generations since O’Connel’s time. I remember the famine. Do you know that the orange lodges agitated for repeal of the union twenty years before O’Connel did or before the prelates of your communion denounced him as a demagogue? You fenians forget some things. (James Joyce, Ulysses. Penguin Books,1992. p. 38)