You pull your shirt up and over your head, throwing it over into the passenger seat before slipping your too big shoes off and throwing them in the passenger floor board.
You adjust your seat a little before starting your 25 minute drive home. Since you didn't read the warnings on the label you have no idea the 20 years of your age sitting in your cream on your shirt is slowly expiring.
5 minutes from home the 20 minutes are up, cells starting to multiply in the middle of your shirt, quickly doubling over and over again.
As you pull into your garage you don't notice the movement in your shirt, but just as you are about to climb your 16 year old body out of the car you start to hear crying. You reach over and lift your shirt up, amazed to find a newborn baby hiding there.
"Where the hell did you come from?" you ask as you pick the babe up in your shirt and take him inside. With each step he feels heavier and looking down you see a full head of hair on a three year old looking up at you, looking strangely familiar.
The child is getting heavier and heavier by the second so you lay him on the couch. You watch as he grows older, getting longer, and looking just like you did as a kid.
He groans as he sits up, balls dropping as he hits 13, hairs quickly starting to sprout from his maturing crotch. Soon he looks exactly like you, then surpasses you in age as his height increases, muscles grow, chest hair comes in, manhood full size and bigger than yours.
"Fuck that was weird." your twin says looking at you. "How did I get home, and who are you? Last thing I remember is jacking off with some cream in the car..."
Both of you look at each other, then speak at the exact same time "Maybe we should go read that bottle!"