So, with the influx of streamers getting to 5.3, I've watched the Elidibus cutscene a few times recently, and I've noticed that when presented with the crystals of the convocation, he clutches the crystal for Igeyorm and Lahabrea. Considering that Pandaemonium was likely in the writer's mind at this point, I can't imagine this is just a throwaway. Considering the link between Igeyorm and Lahabrea, as was shown in Heavensward, I can think of two possible avenues they could go.

1. Athena is not actually dead and is actually Igeyorm, and the current and past Lahabrea are the same person (Unlikely, but not impossible I think)

2. Ericthonius becomes the next Lahabrea, and from maybe Abyssos, we have another Ancient tag along with the Themis-Eric duo (possibly another warden from abyssos who would serve as the P5 boss) who subsequently becomes Igeyorm. Although I personally don't like thinking that Eric becomes the maniac we see in ARR/HW, I feel like this is the more likely of the two theories, as Pandaemonium would establish a link between Elidibus, Igeyorm and Lahabrea, while also possibly having a side love-story associated with Lahabrea and Igeyorm.

I apologize if this an already covered topic, but I haven't seen anything along those lines so I just decided to throw this out there.