Before I worked with Daniel on That Cool Robot, I collaborated with Paper Jam Comics Collective member Iain Milne. This first of these was called The Wolf Wrestler and appeared in You will Have To Wait... And That.
The intention we had was for the guy making the phone call to be calling in a hit on himself. He considered himself such a failure, to his wife, family, everyone, but we never go into why. We do know that he can't bring himself to kill himself, at least not directly, so he hires someone else to do the job. The twist is in the end with the mugger threatening him with his stanley knife. Does he save him the bother? Or is this confrontation with death for real enough to turn his life around?
I'm not sure it's entirely clear that the guy in the phonebox is hiring the hitman to target himself. I think people reading it at a glance may assume that the target is a third man, but to be honest, the comic reads well either way, with the conclusion still having a bit of poetic injustice to it.