They're just amoral, no worse no less. They're just demon capitalists and aren't interested in doing evil for the sake of it, especially when doing "good" profits them a lot more :D
[@Background Pony \#6242](/images/2741225#comment_9884274)
[@Background Pony \#399A](/images/2741225#comment_9884406)
He's actually cheating the system in a way. He summons them for such small tasks that he recovers life force faster than he's spending it so, in a way, it really isn't costing him anything. Their queen is okay with it for three reasons and keeps sending Kim for three reasons: One is that wants summoning to become a familiar concept since she figures it'll lead to far more people summoning them, two is Kim's been a bit of a pill at work lately and needs to lighten up, and three is because she honestly thinks the whole thing is funny as hell :P