The ornament has been sitting in the same place on your desk since you realized it was there. You still have no idea where it came from, only that it's here and there's something special about it.
This doesn't narrow things down anywhere near as much as it should.
In the time that you've left it there, it hasn't really done anything. It looks pretty, in the context of something sitting on its own. You aren't sure it would look good on you. Or if you should be trying to wear it in the first place.
But you can't just leave it there.
You don't know why, but it feels like it'd be wrong to do that. Like whatever's important about it, it's too important to leave behind. You have even less idea where this feeling comes from than usual, but you don't want to ignore it. Just in case it turns out to be something that will save you a lot of difficulty later.
You pick it up. It doesn't feel quite like glass, but that's the first guess you have as to the material it's made of. Assuming it's a material found in nature to the first place. It's colder than if you left a drinking glass out at room temperature, and your fingers slide over it easily, with just enough friction that you don't drop it.
If you did drop it, something tells you it wouldn't break. It feels sturdier than that.
Like it was made to be thrown around.
It throws light around pretty well, but you're not going to do any tests with that. You know better now. Refraction and Kouha are a bad mix.
This is all the information you're likely to get just by holding it. You turn the ornament over in your hand, watch as the light scatters to different parts of the room, and take a breath.
And put it on.
...Nothing really feels different. Maybe if you got someone else to scan you while you wore it, you'd know what it does, if it's something that effects the person wearing it. And you're going to assume it effects the person wearing it, because why else would it be made to be worn?
You give it a bit longer, and keep wearing it while working on your homework. Nothing changes.
You conclude that, whatever effect this accessory has, it's either benign, or incredibly slow-acting. And that's about all you can figure out about it, without either asking someone else or doing risky experimentation. You aren't sure you're ready for either of those things right now.
...You also aren't sure you're ready for the full moon.
There's one obvious reason for this: It's the worst possible day it could happen. Even ignoring the stories about the last timeline as something that couldn't happen in this one, it was never going to be a good day.
And that's the reason you can easily give to others. Another, equally pressing issue is that you have no weapons with origins you can explain. Wherever the Nihil Spear went, it hasn't done anything to reveal itself. You still possess the Treason Couse, but if someone asks you where you got it, you're not sure what you'll tell them.
Assuming anyone bothers to ask. You never said anything that time Akihiko-san decided to wear Jack Frost and Pyro Jack puppets into Tartarus instead of actual boxing gloves.
But if you did ask, you think Akihiko-san would be able to answer where he got them from. Your spear isn't even the only unexplainable thing you own!
So that's the bad news. The good news is, if any of those reasons make you feel like you should sit this out, it's unlikely anyone would have a problem with it!
...Do you think you should sit this out?
[ ] You have a lot of reasons not to participate. So you won't. The others will be fine without you for a night, right?
[ ] You'll go, but purely in a support capacity. Still, even if you have a reason for it, not carrying a melee weapon is more likely to give you odd looks than carrying a strange one.
[ ] You'll go, carrying the Treason Couse. You just have to hope the night is too busy for anyone to ask about it, because you have no idea how you'd answer them.
[ ] You'll go, both carrying the Treason Couse and wearing the strange ornament. It's likely you'll come under scrutiny, but... maybe it'll be worth it to find out what it does? If you can figure it out here, anyway.