The moment at which you realize you’ve transitioned from “youth” to “adult” in the eyes of the average person can be a tough one. It raises questions with answers you may not be ready for. Your entire worldview is shifted.
At least, that’s what they tell me. Some of us, myself included, are capable of just coasting on our boyish good looks for many years into adulthood (until the day that we’re horribly disfigured in an aging accident).

Is Greg about to eat that whole turkey in the last panel?
He's certainly about to try…
i laughed at 'aging accident'…