It took me a week to prepare for another ritual. The changing of those runes in the ritual was not the main problem but the resources required to do the ritual were. Even though I gained a lot in those seven months of adventure, my worth didn't increase as much as to support two back-to-back summoning rituals.
So I had to sell a lot of monster corpses that I gained discreetly. I dared to do that because of my new skill, Scent Recognition. It can store every scent that I inhale, either on purpose or naturally. So it was easy to spot the family spies that followed me into the market. It also made it possible for me to escape their eyes easily.
Even if there was no ritual, I would have to sell most of the loot that I gained and turn into something that can be useful for a long time.