Starting on November 3 of this year, adult-only zones will consist of 9 XL seats with extra leg room and 93 standard seats, Corendon shared. These seats will be separated from others via walls and curtains.

Reserving a standard seat in the adult-only zone will cost passengers €45, or about $48, and €100 for an XL seat, or about $108 one way.

And you must be 16 years or older to sit within the zone. 

Source: https://www.buzzfeed.com/alexalisitza/airline-creates-child-free-zones-reactions