Are spirits obligated to keep there pacts?
Is there a way or a pact that they are obligated to keeep?

Pacts are an agreement between you and the spirit. Think of it like a business contract. They will fulfill their part, as long as you fulfill yours. They are “obligated” to keep the pact only as much as you are.

The way I understand it, demons are concentrated power. Thus are a tool for the magician. Another way to look at it would be as a hammer. A hammer will help you build a house as long as you hold up your end of the deal by using it during the construction. If you stop building, the hammer stops working… Just my thoughts.

Edit: Another thought… A hammer isn’t like a demon in the way that a hammer won’t crawl all up your ass to make sure you hold up your end.