The first time they notice it, it is because one of Yata's stupid decisions.
Eric's guard is down. And of course, of course Yata is going to take advantage of this. After all, the whole "English shit" is really pissing him off. It's high time for some revenge.
Kusanagi shoots him a disapproving look, knowing automatically what he is up to. But no one else pays any mind as the redhead sneakily slinks over behind Eric, ready for a childish -but effective- scare. The blond is still skittish, he knows, even now, so what better way to get revenge?
Yata snickers. This is perfect. Like a cobra, dangerously coiled and ready to strike, he positions himself directly behind Eric, who is still staring off in space.
One...two...three!
He shouts.
It is less than one second before Eric reacts, violently jumping up and directing a hateful glare at the laughing Misaki.
But it is what he does next that makes the rest of the bar take notice.
He growls.
It's not like a human growl, either-it sounds so much like an actual dog that for a brief second Kusanagi is ready to yell at Kosuke for bring home another stray.
But no, it's just Eric.
The angry blonde mutters something in English, probably an insult directed toward Yata, and then returns to his previous position, albeit a whole lot more paranoid than before.
Yata only blinks, silent for once, before bursting out into more obnoxious laughs.
So worth it.
And that is the first time they notice Eric's habit of growling when startled.
...
The second time this habit occurs, it is on a less friendly playing field.
They're fighting those "frickin' blues", and everything is going perfectly fine until one certain Fujishima Kosuke is stabbed in the arm by a SCEPTER 4 member.
It's not a deep wound, by any means, but it's enough to make Kosuke stumble back a few steps before going to retaliate.
But he never actually gets to retaliate, because before he knows what is happening he is cut off by a flash of blue and blonde and the feral growl of what could only be a wild animal.
Except it wasn't.
And suddenly his previous attacker is retreating, the blue uniform marred by the distinct mark of Homura flames.
Kosuke gaped. Kusanagi grinned. And Eric only frowned, shooting an unreadable glance at Kosuke before disappearing back into the heat of battle.
And that was the day that all of Homura agreed that Eric was, indeed, a dog.
...
But at least he was their dog.
(Because honestly, no one wanted to deal with a furious Eric.)