TIFU by wearing a pineapple shirt

I go thrift shopping every few weekends and I recently picked up a nice summer button up shirt with with a repeating pattern of pineapples. Each row of pineapples alternates in orientation from right-side-up to upsidedown (this is important). The light yellow plays well with my skin tone and the fabric is thin, soft, and has some weight to it. All around a great find.

It's been fair weather lately and the office I work at has a pretty lax dress code so I figured I'd wear it.

I make it to lunch and shortly after one of my coworkers swing by my desk. I'll call him Brian.

Brian: "Hey, awfly brave wearing that shirt to work, I like it."

Me: "What do you mean? I thought this would fit the dress code."

Brian: "Oh it does, do you know know the symbolism behind it?"

Me: "Behind what? The pineapples!?"

Turns out pineapples, particularly upsidedown ones, are a symbol for swingers and I've been inadvertently advertising to my coworkers that I am one. Thank god I wore an undershirt.

TL;DR: I didn't realize an upsidedown pineapple is a symbol for swingers, wore this shirt to the office and inadvertently advertised myself as a swinger to my coworkers.