Another solution, if all words can be put in a hash (escaping any special regex characters):
#!/usr/local/bin/perl -l -w

use strict;

my %repl_words = (sadboy=>'badboy', sadgirl=>'badgirl');

my $re = join('|', keys %repl_words);
$re = qr/$re/i;

my $str = "this SadBoy and SadGirl are...";

$str =~ s/($re)/fix_case($1, $repl_words{lc($1)})/eg;

print $str;

sub fix_case {
 my $match_word = shift;
 my $replace_word = shift;
 my $i = 0;
 for (split '', $match_word) {
  next if $_ eq lc;
  substr($replace_word, $i, 1) = uc substr($replace_word, $i, 1);
 } continue { $i++ }
 return $replace_word;
}

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In reply to Re: Case-sensitive substitution with case-insensitive matches by runrig
in thread Case-sensitive substitution with case-insensitive matches by Anonymous Monk

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