People often talk and behave as if someone can get power for serving the demonic agenda; but they never can. What they can get (for a while) is pleasurable rewards for self-subordination to the demonic agenda.
For example, someone may pledge (explicitly, more often implicitly) to serve the evil, demonic agenda - and in return he will be rewarded sexually, or in terms of high salary and social status. This trade is perfectly normal, mainstream - and applies to the great majority of successful people in The West.
But - whatever their initial hopes or motivations, and whatever their short term pleasurable payment - such people do not actually get enhanced power; they never get to impose their own personal agenda on the world.
Demons are not that stupid: the one thing a demon will never yield is power over himself. He will never allow himself to be harnessed to a weaker person's agenda - because that, by definition, can unilaterally be made irreversible.
Selling your soul in return for the reward of power is therefore always a trick - in both the short and long term. It is, in fact, a bait-and-switch - where instead of power the person is given pleasure (i.e. something they crave - often sex, perhaps revenge).
(Among and between those in service - control is 'hedonic'; by fear and lust, sticks and carrots, threats and bribes. Escape is always possible; but requires repentance - and repenting typically entails immediate hedonic penalties.)
The end result is always that the self-enslaved power-seeker lies to himself that in being compelled to serve the demonic agenda - in doing what is required of him - he is 'really' doing just exactly what he most wants to do.