This is something that can be called a , which is explained in this question: Origin of ?
You can see more examples here:
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They often wore coats full of difficult kanji like this. This type of creative ateji is basically unique to the / culture in the Showa era. Today, almost no young people do this seriously any more, but you may still see this type of ateji in fiction. The user of is not directly related to , but this ateji seems to symbolize his rough but mannish and upright character.