Small crane
I knew exactly why he looked so horrified too since it had to do with one of the rules associated with chakra beasts. The rule basically went that the amount of chakra that a beast had was directly proportionate to it's overall power. In other words the little ball of fluff in my pocket was going to be S rank at maturity at MINIMUM. By comparison that meant that the little one could square up with a Kage easily once it grew up. Naturally you can understand how terrifying that must seem for the old man.-
Add on whatever ability the little fluffball had and I effectively had an army destroying level of power on my hands.
"In any other circumstance I'd see the beast killed before it could mature into a threat to the village like most other chakra beasts of similar levels of chakra. Fortunately the beast is imprinted onto you and with your command over beasts I need not worry about it rebelling and becoming a problem. That leaves us with a more unique set of problems however as we need to discover the beasts talents, diet, abilities and species to maximize it's training. I trust that you'll come to me for any needs you may have regarding this beast as I am willing to give you my full support in raising it since it has the potential to be a massive boon to the village." the old man said seriously and I nodded.
"First things first I need to know what this this even before I can ask for anything." I said honestly.
"Indeed, I'll speak with Tura Kazeyama about it as the Kazeyama family is the primary supplier of our message hawks and may know more about what species of bird that is. While I handle that why don't you go an introduce the little one to the rest of the village since it's imperative that it become comfortable here?" the old man suggested and I agreed.
I've never had an issue with any of my beasts misbehaving around the village besides my cat that had a habit of stealing food but even in that case I was pretty sure it only did it for the fun of it since it only stole food from shinobi. There was something amusing about seeing a jonin chasing a cat after it stole a sandwich from them.-
Despite this stellar record of behavior I admit that this little one may prove to be an exception since it was bound to imitate me as it matured. I freely accept that I was not the best at behaving in public since I was fairly blunt in how I did things. I wasn't the sort to just act nice when I disliked you and that gave me a bit of a reputation in the village as being standoffish. There was nothing for it really as lots of the village mistreated Naruto and I as a result didn't like them.-
Don't get me wrong there were plenty of people who didn't care either way about Naruto but most of those either didn't experience loss from the nine tails or simply couldn't bring themselves to hate a child. If I had to be entirely honest it was about thirty percent of the village that were decent to Naruto, twenty percent that didn't care either way and fifty percent that hated him or rather hated the nine tails and by extension him. Add on my personality and you can understand how I might be a bad example to follow half the time when I was in the village proper.-
Still that didn't mean I couldn't just ignore everyone I didn't like and just stick to interacting with the people I liked. As I walked through the villages busy streets the little one curiously looked around with it's head stuck out the top of the pocket which earned me more than a few strange looks. The women of the village were practically trampling over each other to say hello to it though. Not that I could really blame them since most woman had a soft spot for cute things and the little fluffball definitely counted.-
Surprisingly the baby bird was perfectly well behaved and didn't peck any of the women trying to pet it. That said it was rather timid and hid in my pocket fully shortly after the swarm of women started getting noisy. I couldn't help but smile at this as it was truly adorable. Once it became clear that they weren't going to get to pet it the swarm dispersed though they waited nearby to try and get a chance at loving on the bird. The little one stayed in the pocket though until I walked into Ichiraku ramen.-
"Chee! Chee! Chee!"
The bird chirped loudly once I got into the restaurant and drew Teuchi's attention from behind the counter.
"New beast Kenzo?" he asked with a raised eyebrow.
"Yeah I hatched this little one last night but I haven't fed it at all so it must be hungry." I said honestly as I reached into my pocket and removed the bird from it and set it on the counter.
"A crane chick? Those aren't that common in this part of the land of fire, a bit of crab aught to satisfy it's hunger though." Teuchi said surprising me as he went to work retrieving some raw crab meat.
"How'd you know it was a crane? I didn't even know that." I asked curiously.
"Oh that? Ayame used to be obsessed with the things when she was little. Must have drilled the information into my head a thousand times over from a book she had. Cranes are omnivores but have a particular favoritism for crab. It's why the ramen bowl with crab is called the crane special." he said with a smile as he fed the little fluffball.
"Huh? I must admit that out of everyone you weren't even on my list of people to ask about this little one. Funny how that works isn't it?" I asked and Teuchi laughed.
"That's the way the world works Kenzo, you never can tell just where you may learn something new. A bit of advice about the little one here though. It will need a protein rich diet so lots of meat or insects and some vitamin rich veggies diced up would be for the best." Teuchi said before putting down a hot bowl of my usual on the counter.
I must have cut an odd picture from the outside as I took a mouthful of my food while a crane chick sat on the counter next to me digging into a bowl of crab meat gluttonously. That was how the ninja the old man sent found me after all. I paid for the meal for both myself and the little one that got sleepy after eating and curled up in my pocket without any fuss before heading back to the Hokage building. The old man sighed when I flat out told him that I found out what the little one was from Teuchi but took the news with an amused look in the end.