If you strike a spirit with Energy Aura you get hurt.

If it hits you, you get hurt +4 DV for the Aura, and the entire attack takes the nature of an elemental attack, fire, electricity etc.

But what happens when you get Possessed by such a spirit?

Does all you wear get affected or can the spirit be "careful"?

What if it posesses an object, like uh, a weapon. How much insulation is required to not get hurt while handling the weapon?

And if I have a water spirit with Energy Aura(cold) and use it to cool my drinks, will the spirit be offended?

I think that, yes, the spirit can be careful and not affect your stuff. Just like the spell version of that spirit power does not affect the subject.

And yes, the spirit would be very offended. But if you waste a service for it, hey, it's your spirit money you'd be wasting!

I can see the ally spirit now. Mage is a squatter, but managed to get a rather intact, but not functioning refrigerator into the building. Has his ally materialize inside the fridge and use cold aura most of the day, and materialize outside the fridge with flame aura for the wintertime.