I usually complain about how "spicy" food in Japan are never spicy enough, but this experience changed my mind.
At the local ramen shop, their latest "extremely spicy ramen" had a choice between 1-10, and with my arrogance, I went for level 5 on my first try, after they have warned me. I thought: "I know what spicy is in Japan and it is nothing!"
What arrived at the table was a pool of redness. The rich thick spicy soup covered every single inch of every single ingredient in the bowl, and boy, eating it while it's hot will burn you in more ways than one.
I'd like to say that it was delicious, but the truth be told, my tongue was more paralyzed by the hotness to know better. It definitely didn't taste bad, but I just couldn't tell anymore.
By the time it cooled down, the noodles was much easier to consume, and eventually, I ate everything in the bowl and drank up a good portion of the red pool too.
And the following day, I summoned a demon in the toilet.
From that day on, if a ramen shop offers level 1-10, I'd go for 3, maybe 4 max if I know the shop, with the risk of summoning only a minor-demon the next morning.