I was sitting on a sailboat on Lake Union on a warm Tuesday in May when the ship's captain ran into a problem. We were minutes into the first Duck Dodge sailing race of the season, and the skipper was yelling at his crew to jibe—a difficult sailing maneuver where one sail goes slack and flips to the opposite side of the boat. No amount of rope tugging could put the sail in the correct position. Other ships raced past us. Our boat sat still. Disorder ensued.

"It's stuck on the cooler!" someone yelled. A young woman in khaki shorts freed the rope, letting the sail slide into position and catch the wind. Our cooler snafu had cost us precious minutes. But our captain, BJ, a fiftysomething retired Microsoft employee, seemed more concerned with the temperature of the boat's beer than our scuttled start.

"Keep my cooler closed, you'll waste my ice! C'mon, priorities!" he yelled. Holding the sailboat's wheel with one hand, he laughed. Then he gave a dad-shake of his hips to the rhythm of Luis Fonsi's "Despacito" playing on the boat's speakers.

The Duck Dodge is a weekly summer boat race on Lake Union, but it's less of a race and more of a party. For the next 17 Tuesday evenings, the lake will fill with sailboats as crews pull ropes back and forth and raise and lower and twist sails in pursuit of the weekly prize—a sticker of a duck to put on the winning sailboat's mast. I'd seen Lake Union fill with hordes of sailboats on Tuesdays for years, but I didn't how fucking weird, fun, and welcoming this 45-year-old race was until I hopped on BJ's 42-foot sailboat Discovery.

Each Duck Dodge is divided into four heats, with the fastest boats taking off first and heading counterclockwise around the lake, followed by three heats of progressively slower boats. After the race is over, the sailboats gather in the middle of the lake and tie up to each other so people can continue partying and drinking while also walking from one boat to another.

Discovery was in the third heat, which felt increasingly crowded as we made our way south toward the first checkpoint, a buoy on the Space Needle side of the lake. Soon, sailboats were so close together that it felt like the lake's surface had turned into an expanse of wooden planks and steel railings. A lot more time is spent dodging other sailors than ducks. Captains and crews grew more frantic, everyone focused on getting around the buoy and heading north toward Gas Works Park.

Well, everyone except for three members of the crew of Temptress, a sailboat with a woman tied to its mast. As boats rocked back and forth within feet of Temptress, two women in black mesh BDSM outfits performed. The sub had her arms tied behind her back and to the mast; the Dom was pouring some liquid (sparkling wine?) out of a red chalice and into the sub's mouth. The sub writhed in apparent pleasure, arched her back, and pointed her foot out over the edge of the boat.

No one seemed particularly surprised by what was happening. I might have been the only astonished one. But then again, it was my first Duck Dodge. Up until this point, I had little idea what all of those sailboats were up to in the middle of the lake in the middle of Seattle in the middle of summer in the middle of the week. It turns out sailing is lot freakier than I thought.