This is not Kate Upton

"No, nothing to add. Go ahead, son!" Jeff giggled.

Next Peter wrote into the book:

Give my Dad Jeff the physical appearance of a 20-year old version of swimsuit model Kate Upton.

And just as he looked at his dad, he saw how the later got replaced by a bikini-clad 20-year old Kate Upton in a split second.

"Er, Peter... I feel a bit strange!" he suddenly heard from her in his dad's voice.
"DAD!?" Peter gasped in disbelief.
"Yes! This obviously is me..." 'Kate' began in Jeff's voice as she started to touch herself. "Damn, that book really made Kate Upton out of me! Quick, do something!"