Nijikai
It is common to first hold a wedding reception (inviting relatives and close friends), then holding a “nijikai” and invite the people you couldn’t invite to your reception. It is a much more casual party than the reception itself.
Akiko Yada and Akiko Wada
Akiko Yada is an actress. Akiko Wada is a singer who has a reputation for being, well, “scary.” One of her hit songs is “The one who rings that bell is you.”
Names
The character for “ichi” of Raichi means “one” and the character for “ji” of Ryuji means “two.” Usually, the elder brother would have a name with the character for “one” and the second one with the character for “two.” This is probably another joke about the names being reversed.
Asazumi Ichigo = Strawberries, freshly picked in the morning
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