I remember I was swimming in blue swim briefs back then and spent days on the beach wearing them, so I got a really strong tan. On the last day, we went for a sunset walk and a final swim in the sea before heading home. Before I even put on my swim briefs, I was walking around in my regular underwear, and I gave myself a wedgie to proudly show my parents my tan lines. I said something like, "Look how tanned I am—it looks like I have a second pair of underwear underneath!" laughing at my own joke.
I immediately regretted my own words, and it stopped being funny—my dad, as you might guess, loved the idea. He agreed that I was right, and since I already had my "natural underwear" on, I didn't need to put on swim briefs on top. So I spent the whole evening just in my "second pair of underwear."
Luckily, it didn't last super long, because it was already quite late, the sun was setting, and the place wasn't very crowded—only a few families were within sight.