Suites
The four of them were in first class.
It was the best choice right now, because they would be going for long trips and more importantly, this was not the typical 'first-class' or the type of 'first-class' cabin of yesteryear.
Many airlines had opted to remove the first-class cabins because it took up too much space and it wasn't often used up. Business-class was upgraded instead. While it was not as luxurious as first class, it was close and did not take up as much space as first-class did.
However, the airline they were on, was one of those few that not only retained their first-class cabins, it was upgraded it.
Some planes had first class, this one had 'suites'.*
It was, literally, a room inside a plane.
The suite cabin only had four suites, with each of its suite being separated by a partition that had a door. The four suites were placed alongside the window with two suites on the left side and two on the right side.