When is a bank most enthusiastic? When you owe it money.
Before, to get a black iron user card and to open an account for someone, you'd pretty much have to burn through a week's worth of investment quota with at least 30 credit-points.
But now, when the "bank" realizes you owe it money, it immediately helps you register an account, gets you a card, and reminds you of your debt in one go.
However, when Lu Ping'an saw this card, he saw something more profound.
"What triggered the ability to activate on its own? Was it the defaulting on a debt.... No, that's not it."
Previously, Meow had also skipped out on paying back its debt, but this wasn't recognized by the banking system. The "15% annual interest rate" on the card gave Lu Ping'an the hint and the answer.
"A 15% annual interest rate, doesn't the contract I have with Hua senior sister also have a 15% annual default penalty rate?"
Both are extra expenses of 15% per year, it's almost blatantly obvious.