How to handle properties on a SCALAR based Perl class?

How to handle properties on a SCALAR based Perl class?

In Perl, it's easy to bless a hashref and use it to store and read
properties:
package MyPackage;
use strict;
use warnings;
sub new {
bless {}, __PACKAGE__;
}
sub SomeProperty {
my $self = shift;
if (@_) {
return $self->{SomeProperty} = shift;
}
$self->{SomeProperty};
}
# Or even like this to be able to call $obj->OtherProperty = $x;
sub OtherProperty : lvalue {
my $self = shift;
$self->{OtherProperty};
}
But, I've seen some Classes (from different Perl modules) that, when
dumped, show a simple scalar blessed:
$obj = bless( \$8756489, 'Some::Package' );
Yet, they have methods and properties. The methods I understand, any
subroutine a package can call then will be called when asking a blessed
$object->name. The part I'm not understanding is how they can store
properties. Where are those properties being stored?
Several times they accept things like $obj->property = $x or
$obj->property($x) and can be independent of other instances of the same
Class. Where are those properties being stored?
I know that really depends on the underlying implementation of the Class,
what it is doing or what it is interacting with, and that can actually
answer the question several times (e.g. the object is just interfacing
with another object or connection somewhere and only sending or quering
values to it).
However, if there's a way for a scalar based object to store properties
(like in a different concept or approach to class structure in Perl), I'd
really like to know it.
Thanks in advance for any comments! :-)