If we play with the definition of "first character", Perl will match a number at the beginning of a string:

$_ = "13foo";
if($_ == 13) {
    print "Works\n";
}
__OUTPUT__
Works
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But doing it under warnings gives you Argument "13foo" isn't numeric in numeric eq (==). The ++ operator also has some DWIM magic involved for incrementing strings that begin with numbers (but -- doesn't).

For any strings, you can also use split like this:

my ($first, $rest) = split '', $str, 2;
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You can also play string reversal tricks, if you don't mind modifying the string:

$_ = reverse $str;
print chop;
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