This defeats the purpose of your title, but another approach is hashes:

use warnings;
use strict;

my %storage   = map { $_ => 1 } qw(knife wand bow);
my %inventory = map { $_ => 1 } qw(axe sword shovel);

while (1) {
    print "Which item would you like to deposit?\n";
    print "$_\n" for sort keys %inventory;
    my $choice = lc <STDIN>;
    chomp $choice;
    if (exists $inventory{$choice}) {
        delete $inventory{$choice};
        $storage{$choice}++;
        print qq(You have stored a "$choice".\n);
    }
    elsif ($choice eq 'end') {
        last;
    }
}

use Data::Dumper;
$Data::Dumper::Sortkeys=1;
print Dumper(\%storage);
print Dumper(\%inventory);
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