This is a Kenyan slang
sheng borrowed from the Swahili language meaning nothing matters more than life. It is commonly used when things don't work out as planned or expected.
In some cases, it's used to as a polite way of telling somebody to mind their business.
Pinchez: Maze dem yangu ameleft.
Kevo: Wah, iza bro.
Pinchez: Bora uhai, sindio?
Kevo: Kabisa.
