tie my %flat, "FlatHash";
$flat{Monkey}{habits} = "Eating";
$flat{monkey}{habits} = "Scratching";
warn Dumper(\%flat);
__END__
Ultimately I'd like the final datastructure to be something like:

$VAR1 = { 'monkey' => {
    'habits' => ['Eating', 'Scratching']
    }
};