Mateo sat at his cluttered desk, a heavy textbook open in front of him. His room was dimly lit, the only illumination coming from his desk lamp and the faint glow of his computer screen. Empty cans of energy drinks were scattered around, evidence of his relentless study sessions. The quiet hum of the night was only interrupted by the occasional scribble of his pen on paper as he jotted down notes.

Just as he reached for another energy drink, a strange, shimmering light appeared above his head. At first, it was just a faint glow, but it quickly expanded into a swirling, pulsating portal. Mateo blinked, staring at it in disbelief.

“What the hell…?” he muttered under his breath, shaking his head and rubbing his eyes.

The portal remained, swirling ominously. Mateo, a staunch realist, glanced at the energy drink in his hand. "Great," he said, his voice heavy with sarcasm. "Must be the caffeine messing with my head. I knew I shouldn't have had that fourth one."

He stood up, stretching his arms and cracking his neck, trying to shake off the hallucination. The portal, however, did not waver. Instead, it seemed to grow brighter and more insistent. Mateo's skepticism was etched on his face as he narrowed his eyes at the impossible phenomenon.

"Okay, Mateo," he said to himself, "you're just tired. This is just a trick of the mind. A hallucination. No way this is real." He reached out cautiously, his fingers just inches away from the portal, expecting his hand to pass through empty air.

To his shock, his fingertips touched something solid and cold. He yanked his hand back, eyes wide with confusion and a hint of fear. "What the…?" he whispered, staring at his hand and then back at the portal.

Taking a deep breath, Mateo tried to gather his thoughts. "Alright," he said, trying to maintain a calm exterior despite the panic rising in his chest. "If this is real… what do I do now?"