Seems so. But there are two dates. Where in the pool should we put it?
Hm, I guess I would go with the former? It was published in Pixiv on the 7th, and the joke is basically that even though it's good belly day, the public is looking at the boobs (which would be a day later).
The 7th of November is Good Belly Day
The 8th of November is Good Boobs DayOf course you're not looking at my bellyHmphYou're looking at my boobs, right?