userious interest-rate
A loan-shark's "percentage extra" quote which is so outrageously exorbitant that you incredulously reply, "You serious?!"
In one of comedian-duo Bob 'n' Ray's "Garish Summit" episodes, mob-boss Harold W. Bigg grumblingly opines that the 50% "preferred borrowers" interest-rate that they've been allowing Caldwell Merchfield is too low now that Caldwell has been promoted to a higher-paying job at his family's lead-mining business; Mr. Bigg now feels that an even more userious interest-rate might be in order.