Evil Worshiping Good

[Harleypool]

It is obvious you are trying to go for a unique character concept and your GM is on-board so not going to pointlessly quote "game rules" as it is explicitly stated that the rules are guidelines not The 10 Commandments, pun intended.

To answer what you are really asking I will use an example of a character I had for an evil campaign, which her concept might work for you.

You can have an evil character who thinks they are not evil. In most realistic cases evil people do not see themselves as evil at all. My character was LE who grew up in an evil empire within a noble family. Rebels had killed her family and so growing up from her perspective the rebels (good guys) were the problem with society as they represented chaos and a disregard for authority. (Good) outsiders were trying to destroy her nation and destroy their customs and culture so she felt perfectly justified torturing and killing them as she was working in the service of her king and queen to stop the heathens from destroying her home. If anyone tried to tell her she was wrong she would believe they were simply misinterpreting/twisting the holy word or trying to lead her astray when in truth she had already been led astray and was the one twisting the religious text of her chosen deity.

[Val'bryn2]

It may be an interesting character idea, but it just kind of falls flat in a world where your moral and ethical leanings can be seen with a simple spell. It may work in a world where the gods are mostly absent, but when you have such easy access to seeing the truth of yourself, such denial is almost impossible to believe. Then again, I hear the sounds of prayers to Razmir, so what do I know?

[Asmodeus' Advocate]

Val'bryn2 wrote:

It may be an interesting character idea, but it just kind of falls flat in a world where your moral and ethical leanings can be seen with a simple spell.

Just 'cause my goals aren't aligned with angels and genocidal lunatics like Sarenrae doesn't mean that I think I'm evil. Maybe I think I'm Evil, as in the Evil alignment, and if so I'm likely astute enough to know I'm going to hell. But that doesn't change what I think is right or wrong.

[Val'bryn2]

No, you're just sharing the outlook of omnicidal maniacs like Rovagug, or his 6th spawn, Adventurers.

People may disagree with me, but I find the whole "I may be evil but I'm trying to do good' a bunch of Minotaur dung. Being Good is hard, those "good Catholic monsters" are traitors to the faith (ostensibly, let's not discuss their real world religion), if you claim to believe something, then repeatedly and gleefully live your life in opposition to the teachings of that faith, it's a betrayal.

[Myrryr]

Well, a few corrections to the thread. First off, James has stated explicitly several times over in the campaign setting forum that Pharasma is the most powerful god (more powerful than Rovagug) by a longshot. Rovagug is second, and beyond that it varies, sometimes drastically.

For example, it took TWO Azlanti gods to stop a meteor from destroying Golarion entirely, both died, and the meteorite still caused worldwide damage anyway. And then there's Azathoth who is literally the size of a black hole and the center of a galaxy and couldn't even notice if a million meteors the size of the starstone slammed into him. So deities are simply not always comparable.

If there were no ill-defined godly pact, then yes, those few ultra-powerful gods would just instantly crush all of the others and do with the multiverse what they wanted. As it is, they can't.
Now, as to why the pact exists, or who enforces it, that's not written anywhere, but an easy obvious answer is 'because Pharasma said so'.

Why? Lots of reasons, but no canon ones. Perhaps the godly pact was written by Asmodeus and is filled with minutiae that allows interference in specific circumstances and many different cases. The most likely reason, in fact.

And keep in mind that demigods are NOT held by that pact, which is why individuals like Deskari can invade a world where Rovagug is held prisoner without siccing every single god onto his face like would result if he just had a divine spark. That's the reason why I allow evil characters to be played in WotR, incidentally. Asmodeus and Zon-Kuthon and the like screaming at their clerics to go stop that moronic bug from breaking the Prison open since they can't do it.

Another thing to keep in mind is that there are a lot of gods. I mean a LOT of gods. Golarion alone has three deities (Nethys, Irori and Nalinivati) that have achieved apotheosis entirely on their own as mortals. Four more thanks to the starstone, just written in canon, and just in the last ~10k years. Now expand that to every planet in the material plane with life. Even if you only got one god out of every 10 planets (and ignore the fact that the material plane is explicitly called out as being infinite in size in The Great Beyond), there are still Trillions of gods out there before you even start to look at the other planes.
None of the gods, expecting possibly Pharasma, are omnipotent, so can you imagine a cross planar universal war between trillions of what basically amounts to Superman merged with Doctor Strange? Kind of a neat thought, but 'chaos' is the only words that truly comes to mind and then... only the proteans win.