The following morning

The next morning, Seth woke up at 10:30, his cock rock-hard. "Holy shit," he muttered, eyes widening. "I don’t think I’ve ever been this hard," He sat up and pulled the blankets off, revealing his erection—bigger than it had ever been before. "Was the serum still working yesterday? Did it just... kick in now?"

His cock throbbed, and he couldn’t ignore the intense pressure any longer. He grabbed his shaft, stroking himself slowly, moaning quietly. He continued, feeling precum leak from the tip as his breathing became heavier.

"Shit!" His hips bucked instinctively as he increased the pace.

*Knock* *knock* *knock*

Are you ready yet, Seth? We were gonna go to the pharmacy, remember?" Mia’s voice came through the door.

Seth groaned as he felt his balls tighten. "Ugh, yeah, I’ll be out in a sec."

"Come on, hurry up!" Dakota called impatiently.

"Hold on a sec!" Seth shouted, trying to fight the pressure building inside him.

"Come on, man! I had to get up early on a Saturday—so can you!" Aaron added, his voice muffled through the door.

"Oh shit," Seth moaned.