About "Ooiri" (ooiri - 大入) :
Ooiri means 'full house'. These kanji are used to indicate that a theatre show is full. The ooiri calligraphy is also used as a lucky sign on various objects. For instance, money gifts are often offered in an envelope baring the ooiri sign.
Traditional printed cloth for packing with the ooiri sign as pattern
[source]A manga character holding an envelope with the ooiri sign (money gift)
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