I'll just say it here since it became the active thread now: 

I made an evaluation on the function of the Demon Guard servitor (not sure if I shared this) and the results were surprising: the demon guard has reduced the number of psychic/spiritual attacks against us by 90%.

It's a fairly simple function which stops attacks by pre-emptively removing the karma the attackers would use as a way in, and the demon guard does this idly, in the background where you normally won't see her work. She can be ordered to perform tasks and I did this a lot in the beginning, but she's not suited for direct frontal assaults, which is why I forgot about her after Tanya and Raid were created.