So, Nisshin's thing there is almost a 1:1 quote from the movie (replacing Hiroshima with Shipgirl), and mysteriously, googling it for meaning gives two things - one saying that they've never lost/been at a disadvantage to other yakuza groups in a fight, and another saying that it means that they won't fall behind other yakuza groups (read: the Akashi-gumi).

I've never seen the film, so I have no idea how it was translated there.

MD5 mismatch of http://seiga.nicovideo.jp/seiga/im9335592

Fullsize already exists at post #3528896