Catching King Boo - Luigi's Mansion

Luigi pondered deeper onto the tiny riddle Bowser had left them with.
“Two heads, five tiles off and three corners out,” he muttered to himself repeatedly, eyeing the two statues, the door from which they’d first entered back and forth.
“Um, Luigi…?” Yoshi noticed the green plumber from the corner of his eye. “What are あなた muttering about…?”
“There’s something about those two statues, and the door that we came in earlier—something’s off…,” he mumbled, not really talking to Yoshi at all.
The green dinosaur frowned. “ ‘Something’s off’? I don’t get it—what...