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If you look closely, the amusement park churros have green stars on them.

The vinyls on Diggin's cover are 7-inch singles. Here's how you can tell:

Only 7-inch singles and 12-inch LPs come in 45 RPM (45 revolutions per minute, a faster speed for vinyls).

You can clearly see the names of some of the vinyls - Yokohama Walker, Shibuya Marble Texture - PCCS - etc., which are the names of the singles, not the albums they came on. (In fact, the vinyls contain each division's first division song.)

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If you look closely at it, the coffee says "coffee" on it in katakana and English.

The name of the song Diggin' comes from the Japanese verb ディグる, itself coming from the English verb "dig". ディグる means "to dig for a record in a mountain of records at a record store", with its origins in DJs looking for a song they like in said mountain. This should explain the song's lyrics.

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If you look closely at it, the canned mackerel says "saba" (mackerel) on it in kanji and all-caps romaji.

The Entry Ticket says "TICKET" in the top left, "DREAM" in the middle and "Toto Dreamland Special Ticket" on the right side.

The Maid Cafe Tissues say "Maid Cafe Dream Dream" on them. (There is also other text, but it's hard to read all of it.)

Discusses (but doesn't show) the evolved cards.

Japanese dog tags are oval in shape, similar to the US's. There are usually 2 with the same information, so that if one is removed, the other can still be used for identification purposes.

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Under the cut because it relates to a roulette outcome.

Under a cut because it discusses evolved 2025 birthday Jakurai.

If you list out FP, MTR, DH or BAT using their first names in romaji, they go in reverse alphabetical order. This contrasts BB, who go in alphabetical order, and MTC, who aren't in any set pattern.

Jyushi's birthday is a play upon his name. His birthdate is the 14th, like the kanji of his first name say, but since there is no 40th month, it happens in the 4th month (April) instead.

(Minor spoilers for the 2025 soul swap.)

Hifumi is (initially) in Ichiro in the 2025 soul swap to make a reference to Good Morning, Ikebukuro.

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Like Gentaro, Soma Saito is also an author of various genres:

His debut fictional work was called "Isana" and it was printed in a literary magazine called Spin in Sept. 2022.

He also has at least 2 essay collections, published in Oct. 2018 and Jan. 2019 respectively.

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