Of course after dying from a gunshot to the head Nacho woke up in a dark place and he heard a voice telling him

“You have two options…you can Either spend the rest of your afterlife in the underworld or you may become a Grim Reaper and collect the souls I tell you too to repel from your sins and live a peaceful afterlife…”

Nacho chose to become a Grim Reaper, so each night he would go out and seek for those souls that needed to be taken to the afterlife