I think it's called 'inside-out'?

No, Net::SSH2 is not an inside-out based object.

It is a wrapper for a C library. The only value objects of Net::SSH2 require on the Perl side is a pointer to the underlaying C structure representing the SSH connection and so a reference to a scalar is enough. That's quite common.

In any case, using inheritance to redefine some methods in a class that was (at least a-priori) not designed to be used that way usually is not a good idea.

A better approach is to use delegation, specially in Perl, where you can use AUTOLOAD (see perlsub) to generate proxy methods on the fly easyly.