I've read chapters 21 and 8. Chapter 21 gave us a horrific murder scene and its aftermath while chapter 8 just gave us middle-aged guy with adrenaline-junky issues and who likes to sleep around.
It seems that the chapters alternate with thread 1 starting just after the middle (chapter 21 out of a total of 40 chapters) and thread 2 jumping all over the place from the first half, so it's not quite as random as it first appeared.
I'm reading up to chapter 4 as a buddy-read with Themis-Athena since we worked out that that was the point where the first book, Vivre au Max, ended. We also now know that Vivre au Max is a TV show and seems to have a sketchy background.
So, what tag should we use? "Vivre au Max"? "French buddy-read"? "Vide buddy-read"? I've never come up with a satisfactory translation of "buddy-read", myself.