Replacing the Magic Rock

This is one of the Magic Stones which guards the city. The Magic Stone itself has been under a spell. Many Monsters must have lost their lives while retrieving it. But they're still obsessed with this place.
Anyway, I need something to replace this Magic Stone. The best way is to ask Alchemist Exerion to make another one, but he won't agree without a generous reward.
I lost a <HFFFA7272>Sorcerer's Pergamena<HFFFFFFFF> in Nocturn Yard before, and I remember Exerion really wanted to have it. Find it and give it to Exerion. You can find it from the gap between the <HFFFA7272>Ruins<HFFFFFFFF> in <HFFFA7272>Nocturn Yard<HFFFFFFFF>. Give it to <HFFFA7272>Alchemist Exerion<HFFFFFFFF> in the <HFFFA7272>West part of the City<HFFFFFFFF> and ask him a favor.

I want to have the document too, but it's okay because I already gave it up when I lost it in Nocturn Yard. So don't worry. Please find the <HFFFA7272>Sorcerer's Pergamena<HFFFFFFFF> in the gap between the <HFFFA7272>Ruins<HFFFFFFFF> in <HFFFA7272>Nocturn Yard<HFFFFFFFF> to give it to <HFFFA7272>Alchemist Exerion<HFFFFFFFF> in the <HFFFA7272>West part of the City<HFFFFFFFF>, and ask him a favor.

I'm busy at the moment! Wait a minute! Take a break there! Oh, what's this Pergamena? Wow! Okay, let's hear what Sorcerer Ron wants since he's done me such a favor. Oh, that's what he wants. This is difficult. Realistically, it's a big favor to ask, but in exchange for this Pergamena...Wait a minute.