Aura: "They are interested in little transparent ball. Find information about it without revealing too much"
Zenjirou: "I've got this!!".
Zenjirou: "Here. Take this impossible to do big transparent but not sphere shaped thingy."
Whatever secret the prince "blurted out" pales next to the MCs blunder of gifting him with that bottle. The twin kingdom now has an idea of the skills they possess to manufacture something so well shaped and smoothly polished and with zero impurities. If a marble takes roughly decades to manufacture, then that bottle would take a lifetime. And he gave it away.
My guess is that since no one else heard them, this means they can probably deny that they arranged a meeting with the queen. The glass from the whiskey may not be a sphere but it is extremely clear, so while it may not be better than the marble, once they polish it into spheres it may be good enough for them to have a significant improvement over their previous spheres. Also they might be able to make multiple out of it.
@Red225- The hard part isn't melting it or shaping glass, though. It's getting clear glass. If they can melt it, that bottle is enormously useful as material, even if they aren't lying about the 'spherical shape' requirement. Here's the thing - The actual clear marble isn't something they'd be willing to experiment with, because they could damage it and end up losing a valuable tool. A bottle they can experiment on.
I forget now. Can he travel freely between worlds? If so, he can pretty easily shift the power balance in that world with a trip to the local hardware store.
@Sylveran No, so far his wife is the only one that can do it, and she has a year-long cooldown between attempts. Since the MC shares her bloodline he can probably learn the ability himself, but it's not going to be for a while.
You all seem to be forgetting they already started the process to figure out how to make such glass themselves off of what he knew from his previous world.
Maybe one day this MC grows a brain and stops being the dumbass that he is, falling into obvious traps like that. But oh well, he's japanese so I doubt that'll ever happen...
@Sylveran: The thing is, MC did consult Aura (aka., the Queen), and decided to gift them the Glass Bottle, in order to gauge their reaction to it. And just like before with those beads, they showed no interest in it, because to them, that Glass Bottle is just a piece of craft which is unique. What they really want is either Glass Sphere or a Glass Marble.
The only one to show a major reaction to the Glass Bottle was Bona, because she is mad (kind of like an Otaku), about those kind of stuff.
Also, Aura already has plans to
create Glass Marbles in her Kingdom so that she could not only be a big supplier of them to the that other country, but also get exclusive access to there Magic Item made from those Glass Marbles. She plans to do it before anyone else figure out the process, so that she could create a monoploy or a good base for herself in this business.
As for the World Transfer thing, only Aura can do it presently, and its something that can't be done easily as many stuff are involved in the process like right star constellation, time, huge mana demand, etc.
Currently the next time that Aura can use her World Transfer magic is around 30-40 years latter, because of all the factors.
But there is a small plan of MC
were he wants to open a small, low cost world connecting portal, to allow radio waves from Earth to reach to this World, so that he can access Internet again.
MC cannot get mistresses due to the earlier "peace" contract/agreement. Twin kingdom fear his children will have both royal types of magic - bestowal and space/time.
@Lichon: Actually, MC can get mistresses based on that very contract, but the clause states that if a child is born with Healing Magic, and belongs to a mistress side, then they have to send that child to study for a few years in that Twin Kingdom, and if that child after that wishes to stay in that Kingdom, then MC and Aura can't act against it.
But because of the nature of the contract and the involvement of two bloodline magic, Aura has to try and be careful to not allow MC's blood (aka., his child) fall into some other families hand, as it could political issues (so she has to be careful at selecting MC's mistresses).
As for the fear of having two bloodline in one person, that isn't what the Twin Kingdom is worried about.
What they are worried about is loss of customer and monoploy due to another Kingdom getting access to their exclusive Bestowal Magic, because it is their own unique magic which makes the Twin Kingdom the only nation which has the highest magical technological advantage over other nations. If the child is born directly to MC's Royal family, the issue could be contained somewhat, but the situation changes if the child is born to a mistresses.
The writing is surprisingly clever here. Both sides feel like they're both getting the upper hand, and getting played at the same time.
Still, once they're able to manufacture glass themselves, the one bottle they gave away will seem cheap. And even though they made such a fuss about the child being able to use both types of magic, no one seems to be worried that Zenjirou might also be able to learn bestowal.