What spray product could protect paper against grease? I glued a bunch of origami to a paper lantern, like in the photo below. I plan to hang it near the kitchen. But I'm afraid that grease from cooking will ruin it. Is there a product (preferably spray-on) that would protect against grease or, at least, make the lantern cleanable?

I wrote to Krylon, Plasti Dip, and Golden Paints (about their Archival Varnish), but all informed me their products weren't suitable. Plasti Dip said that "the product will soften, and eventually peel away from the surface."

I can live with a slight change in color or semi-gloss look, but don't want it to yellow. I'm using an LED light bulb that gets barely warm to the touch, so I feel pretty safe.
I don't know whether you have finished all of your origami work, but I was just introduced to clear gesso. With this movement of Bible journaling, one of the big problems that they were having was either the drawings bleeding through to the next page or the pages were sticking together with decoupage. They discovered that a layer of clear gesso down on the page first prevented the bleeding and staining problems. This would be a solution to use prior to starting your project though.