If \b matches an invisible area between a word and a non-word character, \B matches the invisible spaces that are between two word characters OR between two non-word characters. For instance, /f\B./ matches "fr" but it does not match "f@" because the invisible space between 'f' and '@' is a word boundary and we are looking for invisible spaces that are not word boundaries. Similary /@\B./ would match "@}" but it would not match "@A".
$PM = "Perl Monk's";
$MCF = "Most Clueless Friar Abbot";
$nysus = $PM . $MCF;
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