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First, to get things clear, what are considered objects here are C structures containing a properly initialised structure defined in ioncore/obj.h as the first element (or the first element of the structure which is the first element and so on which gives rise to inheritance). The WObj structure contains a pointer to a WObjDescr class type info structure and a list of so called ``watches''. The WObjDescr structure simply lists the class name, a table of dynamic functions and a pointer to deinitialisation function (or ``destructor'').
Ion does not do any reference counting, garbage collecting or other fancy things related to automatic safe freeing of objects with its simplistic object system. Instead special watches (the WWatch structure) may be used to create safe references to objects that might be destroyed during the time the specific pointer is needed. When an object is destroyed, its list of watches is processed, setting the pointers in the watches to NULL and the watch handlers for each watch are called.