There is a moment that no one says anything. Eevee and Arcanine stare at Hypno while the yellow Pokemon looks elsewhere, his gaze distant and troubled. Eventually, the fire dog disrupts the silence to ask, "What do you mean by that?"
Hypno takes a deep breath, then releases it, the action long and slow, "I do not know," he raises a hand to stall Eevee's predicable outburst of a response, then gets to his feet.
Hypno makes his way to a cupboard and pulls out a bottle and three bowls. Returning to Eevee and Arcanine, he sets the bowls in front of the two and pours a blue liquid into them. Setting the bottle aside, he picks up one of the bowls and takes a drink. When he lowers the bowl again, he notices Eevee and Arcanine are just looking at him, "Forgive me. I needed something to settle my stomach. But, please. Drink. This berry juice was made by Shuckle, our local expert, using berries grown here in River's End. Something about berries grown by the river here makes them great for fermenting. The result is this excellent berry juice."
Arcanine leans down and drinks some for himself. After making a pleased noise at the taste, he looks back at Hypno, "It is delicious. Thank you. But why did you need to settle your stomach? Was it that disturbing?"
The Psychic-type sighs, then shakes his head, "No. I am not queasy, as one might expect from my reaction. Simply brushing the primal hunger in you made me feel ravenous. But not a mindless ravenousness, most curiously."
"Like you could go hunting, catch someone, taunt them, and then derive some sort of pleasure from eating them?" Eevee offers, to which Hypno nods.
"Yes. Not unlike your first encounter with Arcanine," the fire dog's ears droop at the reminder of what he'd put Eevee through, though Hypno continues unabated, "It was... overwhelming. I could only think of distancing myself from that hunger, lest it consume me. Whether it could or not mattered not. As such, I learned little of its origin or nature. However, I believe I know why it wasn't found before now."
"How?" Arcanine prompts.
"Just before I encountered it, there was a... disconnect. A separation. In short, you have, whether intentionally or not, hidden that primal hunger away and have tried to separate yourself from it. Guarded yourself, and everyone else, from it as best as you can. Under the influence of my hypnosis, that guard slipped, revealing the 'path,' so to speak, to that hidden hunger. I imagine, should I have wanted to, I could have used that to provoke that hunger. Make it manifest in you here and now."
More silence met Hypno's revelation, then Eevee questions, "So what do we do about it? Can you remove it?"
Hypno takes another sip of his berry juice, "I do not know. I would have to delve into Arcanine's mind some more to figure out exactly what we are dealing with. Which comes to the answer to your former question. I would like you to come back some other time so that we may do this again, Arcanine. Not today or even tomorrow. I shall have to rest after today's encounter. But I would like to help you. If I can."
Arcanine nods, his expression brightening, " Of course! This is the closest I've gotten to figuring this out!"
Hypno nods, then turns to Eevee, "Eevee. From your memories, I know you possess a reviver seed and are familiar with what I am about to request. I would have you remain with Arcanine. In the event that hunger overcomes him and he has another episo-"
"Absolutely not," The bright look had abandoned the fire dog's countenance, replaced by a disapproving scowl, "You are asking him to be a-a sacrifice! No!"
The Psychic-type shakes his head and takes another sip of berry juice, "Should you have an episode and be overcome with that primal hunger, you will eat anyone."
Recognizing the point Hypno is making, Eevee jumps in, "Which would you prefer? To eat someone aware of your problems and who will come back? Like me? Or someone who has no idea and will be gone after your digest them? Like Kangaskhan's daughter? Do you want to explain to her about what happened to her baby? Do you think she'd believe that it wasn't your fault, even with Hypno vouching for you?"
Arcanine hesitates to respond, allowing Hypno to note, "An apt comparison, if a harsh one."
Arcanine shakes his head, "But I only have so many reviver seeds. Once I'm out-"
"Forgive my interruption," Hypno interrupts, "But I can provide seeds as needed. Especially for a situation such as this."
Eevee nods his thanks to the yellow Pokemon before returning his gaze to Arcanine. The canine hesitates again, then sighs, "Alright. Fine. But don't blame me about it hurting or me being cruel."
Eevee gets to his paws and pads over to Arcanine. He butts his head against the fire dog's leg with a sly chuckle, "I would never. At least, I would never actually mean it."
Arcanine gives an irritated huff, "And yet again, you push me into being uncomfortable."
"Only so I can help you," Eevee replies, failing to keep the snideness out of his voice. Arcanine just huffs again.