The Pugilist Society is the 'fight club' of underground society yore.

The Black Eye as both a badge of honor and dishonor, (reward as acceptance (hazing/gang beatdown- punishment for breaking the code.)depending on which eye you see it from. (kek)

Like the masonic play where the initiate would have a noose around his neck, one trouser leg pulled up, etc, while being threatened to have his intestines cut out and thrown over his shoulder and so on...as warning to not break the code of silence.

As punishment, a black eye would typically be a misdemeanor with continuation in the club.

Always with an eastern counterpart, it symbolizes a larger fight.

https://www.britannica.com/topic/Boxer-Chinese-secret-society

btw: In the movie 'Fight Club', Tyler Durden is the fragmented, compartmentalized personality of an initiate being mk'd. He and his complimentary adversary are one and the same.

https://www.facebook.com/FCBullyTeam/photos/?tab=album&album_id=1324749767623939