STLC stands for Sweet Tittie Loving Christ. Generally something shouted in a moment of excellence or awesomeness. Or something groaned in a moment of shit getting worse.
Brett says, "STLC!!!!!!!"
Adam asks, "what the hell are you talking about?"
Brett replies, "STLC.... Sweet Tittie Loving Christ? I'm saying it cause check out dem bitches walking by.
Adam acknowledges, "Makes sense now. I don't believe in Christ, but I certainly wouldn't waste time with a Christ that doesn't love the tits."
Brett agrees, "Damn right."