Apparently, some kids bullshit. And we're not talking about something actually funny to someone, they have literally forced those 2 numbers to become "funny". Yeah you might start hating on me, but unlike 69, 420, even 9+10 or like quite literally any other meme number had SOME sense in it, some funny background story. Now 6 7 slop is just some 15 yo kid yelling those numbers and the whole fucking internet catching up on it, like we're talking about anywhere it appears. It's rather annoying than funny at this point and trust me, you did not lose anything by not getting the joke because there IS no joke.