[The weapon in question seems like a normal grenade launcher on the surface. It's a heavy thing, clearly something a normal person wouldn't be able to easily heft, and currently isn't loaded. There are three stacks of ammo sitting on the table nearby since he hasn't actually had reason to use it...not yet, anyway.

Despite Vash's own knowledge of weaponry, he may notice that there are things about the weapon he can't quite understand. It seems like it's been tampered with, modified to function on a higher level than it would be able to normally, and the components inside...well, they're Originium, which isn't present anywhere but on Terra. It's a curious thing, and would warrant some questioning, perhaps...

Which may get to happen, because as soon as Vash hits his head on the table and causes it to jostle, Sesa jolts awake with a start. He's lucky he doesn't go tumbling out of his chair wholesale, managing to catch himself with his claws gripping the edge of it, looking around frantically like he's expecting to be attacked.

But there's no danger here. No shadow monsters or Reunion members. It is just......a man.]

Ah- hello? My apologies, I hadn't meant to fall asleep in here, if you needed to use the lab for something.

[Then he notices the screwdriver Vash is holding...and the parts of his weapon that have been reassembled.]

...what are you doing?