Driving to the public pool

Minutes later the three of them were sitting in Martens car on the way to the public swimming area. Martens was driving while Klaus, who was still looking like a teenage girl in a red speedo, was sitting in the back. Next to Klaus sat Walter who was furiously masturbating with his dick out.

"Seriously guys, this is awkward!" Klaus interrupted the scenery."We're supposed to be investigating and you're jerking off to me?"
"I know, but it's so hot to see you like this, your big boobs and your ass, they drive me crazy! I just want to fuck you!" It came from Walter.
"Please don't say things like that, Walter..." Klaus protested.
"But it's true! Just the view of your beautiful teenage ass is enough to give any hot-blooded guy a boner!" Martens chimed in.
"It's still wrong though, we shouldn't say those kind of things about each other."
"That's right! We should focus on the case!" said Walter.
"That's right," said Klaus. "We're here for the case, not for sex. The case is important. More important than this jerk-off session you're doing."
"Fine," said Walter. "But I'm going to think about it all night long and you can't stop me jerking to your borrowed body."
The three drove further in silence until...