Solution is easy - grab them all, and kill them. They're obviously planning to put the blame on you and then blackmail you, so just kill the lot. Problem solved.
@REMasher Probably a slit along the top edge so they can slip in and out; it allows the scabbard to hug the lines of the blade, but it's also a terrible way to construct a scabbard, because it's nowhere near as secure as a full scabbard (speaking from experience, here, as I own a sword with a scabbard like that).
They're probably partially opened on the upper side. Similar to how Machete's scabbard works, they're opened on the whole upper side so it only slides, and just at the end of the scabbard is closed enough to literally just "hold" the weapon.
It helps that way to draw it or withdraw it easily
@REMasher if you look at page 18, the upward part is open so she just need to spin it a bit while sliding it out. I don't remember if Lit actually do this but since she capable of utilizing spirit, she probably used a wind spirit of sorts to help her move her blade better.