"Look, Tatsuki," you say, "removing the seal is like the magical equivalent of surgery, okay? You do not want anyone but a trained, experienced professional doing that kind of job, and you certainly don't want it falling to some random joe with a knife and first aid kit. Now, while I will be the first person to agree that I'm awesome, I'm also eight - that puts me way closer to being the guy with a knife than it does to being the doctor."
She's staring at you. So are the Kurosakis. So is the cat. This... may be good. If nothing else, you've definitely got their attention.
"You need something more than a kid with magical talent for this," you continue steadily. "You need someone who has spent decades telling reality to sit down and shut up, and knows how to make it stick. As a sorcerer, I am telling you that as far as I can tell, you are safe and stable right now - and that may change in a hurry if you let anyone less than a master mess with the seal. Also, as someone I would hope you think of as a friend, I am telling you to think carefully about what you choose to do, because I don't want to see you hurt by a rash decision. And I'm pretty sure I'm not the only one who feels that way."
You nod towards the Kurosaki family. Tatsuki doesn't look where you're indicating, but she does lower her head again. There is a long, tense moment, followed by a short, sharp sigh. She mumbles something.
"What was that?"
"I said, 'fine,'" Tatsuki growls. "Where is this 'expert' of yours?"
"Glad you asked that, my dear," an unfamiliar voice says from right next to you. Tatsuki joins you in whirling in shock - not to mention repressing the reflexive urge to strike out at a sudden, unfamiliar presence getting THAT close - and staring at the skinny old man in his wildly-colored shirt and shorts. Somehow, he contrives to interrupt your half-formed strikes and instead shake your hands, despite the obstacle of his crooked staff. "Merle Ambrose, magus, thaumaturge, seer, sorcerer, advisor to nobility, ally of fairies - hello, little lady" he adds, nodding to Briar, "antagonist of demons, admirer of women, friend to all animals - as long as they aren't biting or clawing me or stealing my food, the ungrateful little wretches - professional vagabond, incorrigible meddler, world traveller, member-at-large of a dozen orders and associations you've doubtless never heard of and that aren't particularly important anyway, regardless of the overblown names they give themselves - and all-around wizard. At your service."
...you suspect that the expression on Tatsuki's face and the emotions that gave rise to it are much like your own. A look, and feeling, best summed up as, "Huwha?"
You hear Altria sigh. "Ambrose..."
"Hmmm? Oh, yes. Japan. Right, lost my head." He lets go of Tatsuki's hand and bows, in a ridiculously elaborate fashion whose only thing in common with the traditional Japanese greeting is that they both involve bending at the waist.
Tatsuki looks over at you, dazed. She's either experiencing serious doubts about your chosen "expert," or else asking you to get her away from the crazy man. Maybe both.
"So," Ambrose says, as he straightens up and looks around at the group, "young Altria tells me someone might have wanted my advice about something - which is, believe it or not, both a remarkably rare occurrence for me, and also NOT the most vague and unhelpful request for assistance I've ever received. As the more polite and patient constabularies are fond of saying, all over the world, what seems to be the problem?"
OOC: Yog's write-in had the most votes, but it was also basically DarkLight's write-in with a few extras. Given that Briar already told Alex that the seal didn't feel malicious at all, having him babble about whether it was good or evil struck me as a little off. Likewise for hinting at the seal having an effect on Tatsuki's basic humanity, when that had previously been voted as a bad idea.