Yeah I figured he'd seem different because of the state of mind and generally, Blood Breeds can control blood and regenerate extremely fast, so that's another tip off.

And thankfully, Leo doesn't do it without permission unless he feels he or a friend of his is in danger, or it's important to a mission he's on, like breaking into a mafia hideout. If either of them ask, Leo would probably show them something they wanted to see with his eyes.