Here is a quote from Vishnu Purana (5.33.46)
"yo harih sa sivah saksad yah sivah sa svayam harih
ye tayor bhedamati sthan narakaya bhave nnarah "
TRANSLATION: Whoever is Lord Hari, He Himself is Lord Shiva indeed. Whoever is manifesting as Lord Shiva, He Himself is Lord Hari. Any human being who mistakes both the Lords to be different, he/she surely goes to hell.
So when we refer Shiva as Demigod - are we not contradicting Krsna? (unlike Brahma and Indra who can be regular souls).
Same goes for RadhaRani - she is Hara, from which all other shakti emanate form, which have no limit - like Durga, Katyayani and Das Vidya. Again I am not talking about other higher sould that are consort to Demi Gods like Indra, Agni, Vayu.
Please shed some light.