There was absolutely nothing that Tank hated more than to be surrounded by people he didn't know. Standing in the line, waiting to be allowed into the compound where his little Lamb was was bad enough. Add on the men, women, and children pushing and crying, and he was ready to snap.
"Keep it under wraps, Hound, or I'll put a leash on you," sneered the demon inside of Dante. The fact that his boss was possessed by one of the Sins wasn't that big of a deal as far as he was concerned, but if Pride thought he was capable of handling Tank, then he had another thing coming.
Hell, even the beast, the Hound inside of him, agreed on that. If the Sin tried anything, the beast would be more than happy to rip him apart and remind him why everyone was terrified of his name.