I don't know about the cartoon, but it can also be interpretted as **cunning plan of the rabbit**.<br/>
So it could be a playword if for instance, the rabbit is trying to suicide with a very clever plan (or you are trying to kill the rabbit).<br/>
As [Romain Valeri][1] said, the "coup du lapin" is well known when we talk about breaking neck on car accident.<br/>
I saw an exemple here : (I typed "coup du lapin cartoon" on google)<br/>
![http://i-cms.linternaute.com/image_cms/original/296853-un-fakir-ne-ferait-pas-mieux.jpg][2]

It looks like this is a website with many cartoons about a rabbit trying to suicide. It would so be a wordplay about **the rabbit doing a clever plan** and **dying quickly**


  [1]: http://french.stackexchange.com/users/1186/romain-valeri
  [2]: https://i.sstatic.net/pqFxP.jpg