My plans, at their current stage, as far as revenge went, were simple. I needed more power, much more power, and for that, I needed to eat. As simple as that. Since adventurers didn't seem to be a good source of abilities, that left me with monsters. And if I needed to remove any of my abilities in the future, I would use that opportunity to test out Pest's possibilities.
For now, I was happy enough to have him as a personal encyclopaedia, and even that when I couldn't ask Rosha the same thing. She was very knowledgeable about monsters, and especially about what materials one could get from them.
As for how to get to Heaven, Rosha told me that clerics and wizards are most likely to have spells in their class abilities that would be even close. Clerics because many of their spells summoned energies and creatures from Heaven in battle, and wizards because they had the most of different spells in general.