As for Orange, I set her up in the update to have different cutscenes depending on whether you are human or infected. You should be able to see the scene where you get swallowed into her giant mouth if you go while infected
As for the Audio Player, I just noticed that now. I'll fix the description
Regarding the Katana, it counters enemy attacks right at the moment you equip it as a weapon. Please keep in mind that the effect won't trigger if you keep it equipped continuously