Sushi...my first experience with sushi was in a traditional Japanese Teppanyaki House that also served sashimi and zushi.
Years ago.
I went with a group of friends, we had saki...a fair amount of the same...and then the sashimi and zushi started rolling out of the kitchen...we had opted for the house special which was basically one of everything for each person ($225 per person, saki was separate)...as each piece came out I would use my chops sticks to hold the piece up to the full color poster of possible zushi options and then pop it in the mouth...move on...repeat...
Then my life changed in one mouthful...it was as if I had licked the great Cthulhu's backside...but I am getting ahead of myself...
A long ceramic plate came out with a series of gelatinous bright green sections...I snatched up a full piece, leaned over to the poster, and looked to place just what it was...I did not find it, and then I noticed the staff looking intently at me...my first clue, one that I did not catch until much later...so I stood up and walked to the main board that had at least twice as many example pictures...still nothing...the server closest to me covered her mouth and tittered, that would be clue number two...this one did not get by without me noticing, but still I moved forward.
Since I could not find out what it was, instead of asking, I sat down at the table...all eyes on me (no one else had touched any of it, that should have been clue number three, alas...)...and popped it into my mouth.
Instantly my world crashed around me...a metallic taste mixed with the flavor of bile and what I would imagine whale vomit to taste like...I tried to swallow but my body violently disagreed, and it popped out of my mouth (whole by the way, it looked the same as it had going in)...I was scraping my tongue and swallowing down bowls of saki to get that foul taste of...yes just what was it?
Then the tittering server told me..."Oh, you don't like shiokara konowata?"
It looked a bit like this, but with more width to the threads
Fermented rice, heavily salted, sea cucumber viscera...cured and minced sea cucumber internal organs...
So nasty that it is a challenge food for hearty Japanese eaters who would normally not even bat an eye.
My life was never the same...for that day forward my hair was peppered with pure white strands...I think I may have aged prematurely...I highly highly recommend that if you see anything like this, do not eat it.
Or eat it...it will make a great story...if you survive...or still have the ability to speak.