Well, if there was an event were Gorgulu becomes All Mighty Gorgthulhu and consumes all of the Demon Lords, it would be nice to bond with all of the Demon Lords and only deepbond with Gorgulu.

I can totally picture it. Gorgulu has absorved all of the Demon Lords and you can actually SEE every other Demon Lord growing inside of Gorgulu

kinda like this



And where in each room where a Demon Lord would've been, there's a tendril instead, with a Demon Lord growing out of it, and when they are close to dying, they go back to Gorgulu. When all four are destroyed, Gorgulu appears, with all of the Demon Lords attached to him attacking in an epic Battle imagine the numbers required to defeat him! Gorgulu would actually fuse with the Taint of Nil and everything would become part of Gorgulu
Something similar with the Supernals. Maybe they offer to sacrifice each other to create a true agent of the Light, where everyone will have a small part in the persona of this agent, but in the end, Raziela becomes the dominant personality and twists every teaching of the Light with his own, to the point, Raziela actually becomes the Light as a tangible thing, which is herself and becomes a major bitch, like Galadriel when tempted to take the One Ring in the movie. "All shall love me and despair" Something like that.

Hmm. I need to pick up FMA again.