Maybe you could explain it away as Jack being ill / recovering from something like amnesia, but yeah I look forwards to future games~!
Oooh, nice! I do feel like all the living organisms in this particular world would be a little... ill-ish. Appended to lore! But if it impacts negatively on the game play experience I should be a big girl and adress it accordingly.
And I shall force myself into more gamejams to motivate myself into bringing more games into the world.
And also looking forward to more Grim Gauntlet Adventure Time!