In case anyone is into this sort of thing, they are bringing in whole blue fin tuna to Mitsuwa this weekend. You can buy any part of the fish, including scraps for “cheap” that you normally can’t get anywhere else. It’s an absolute madhouse but a really good time, and for not too much money you can absolutely gorge yourself on toro.
Here’s a video I found of a previous event if you want to see what it’s like. https://www.youtube.com/watch?v=dPkimSsIC6A
One disclaimer: Although I saw the sign up at Mitsuwa when I went last week, I am unable to find any online information regarding this event.