Emotions will be displayed as: text {emotion}
The Assistant is probably a young man, who's very introverted and socially-awkward. He finds it hard to live in the open word without anyone leading him. But he can still distinguish between good and evil and gets scared when his master wants to brew the dangerous potion. He is kinda desperate because he can't deal with the situation himself and he's scared of asking other people (including the player), also because he can get into trouble too.
Dr. Essren is some kind of fanatical scientist. He has just a few lines, so deciding his personality is quite hard, but I think that you can imagine him like a regular amateur scientist, who got seduced by the vision of power that the forbidden potion can bring him.

	[1/5] The Assistant: Heeh...stranger. I...may need your assistance... {shyly}
	My master...wishes to create a very dangerous poiton... a transformative elixir of invincibility... {worried, quite, still a bit shy}
	I was...in support of this... but then, he accrued essence of... the corruption. I had to run away... {worried, urgent}
	I fear... that he may be going... too far. I need your help... {finding it hard to find the right words, pleadingly}
	Get me... [8 Red Mushroom], they can be found outside the east gate behind me. {a bit like he's trying to figure something out in the beginnging, then faster and clearly}
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	[1/5] The Assistant: Good...good. You have the mushrooms. {hopeful}
	You must...ensure that it has worked. You are much stronger than I. stranger... {hesitantly, a bit scared of player's reaction}
	Did you see the orange witch hat roofed hut when you were gathering the mushrooms? {urgently}
	That is my master's house, you must go back out the east gate and enter the hut. {urgently}
	Bring me his...coat as proof...of his death... {hesitantly, quiet at the end}
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	[1/4] Dr. Essren: Ah, you must be the one my assistant told me about. {mockingly}
	If you are trying to stop me, it's too late. I already drank the pot- {triumphantly}
	What is this taste? Mushrooms? This can't b- {surprised and angry}
	Aa||a|||||gg! {furious tone; original text: Aaaaaarrrggg!}
	
	[5/5] Transformed Essren: What have you done to this potion, human? You will pay for it! {angry, insane subtone}
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	[1/3] The Assistant: I...must thank you, stranger... {quiet, thankful}
	I only hope... that my master will not be...angry with me about this. It...was for the better. {worried, hesitant}
	Now. I...do not want you saying anything about...these events. Take these, and...never speak of this again. {quieter; and a bit hesitant, firmly at the end}