Fun with Loan Calculators

As typical accounting nerds my coworker and I were sitting around at my desk messing with loan calculators. Yeah, fun to the most abnormal human beings.
"Why don't you see what M's monthly loan payment will be to pay it off in 20 years?" My coworker suggested after we calculated his monstrous student debt (a third of ours).
Against my better judgment I plugged in the rough facts and there the loan payments were.
And they were 3/5 of my monthly take home pay.
Cannot wait.