I have decided try to work with permanent glow pigments. I spent part of this week brainstorming: I was having trouble decided what I wanted the picture to be about. In the end I decided on a ‘monster under the bed’ picture, that becomes just toys under the bed in the dark. Here is a sketch I did. 
The glow in the dark pigment is, of course, still visible in the light, so I will work the teddy bear’s face into the shading and features of the monster’s face, but only the teddy bear and other toys will appear in the dark.
I ordered a binder from Amazon and that arrived in the mail early this week, but unfortunately the pigments did not come in until late Wednesday. I didn’t get the chance to pick them up from the mail room, which wasn’t running today because of the blizzard, so I haven’t been able to make as much progress as I would like. After I get the glow in the dark pigments, I need to experiment with mixing and storing them as paint. Then I can do color tests with them on my sketch.
I will be working this week on color tests and further planning using this sketch before I consider moving to canvas (which I will also have to order from Amazon, as the art store CC Lowell appeared to be closed when I visited). I expect there will also be a learning curve with mixing pigments into the acrylic binder, which I will be practicing this week as well.
I like the direction you are heading with this. I wonder if it would make more sense to have the monsters appear in the dark? Good luck with your pigment experiments.
I thought about this actually, because that would be the logical thing to do. But I am a contrary kind of person who thinks rainy days are nice weather, so I sort of wanted to do the opposite. Most people’s stresses (monsters) don’t come from the dark when they get older anyway, they come from what they’re dong during the day, so maybe I’ll do some coming-of-age symbolism hidden in the other toys. Or I could do multiple (smaller) pictures to show passage of time? If you see this let me know what you think.
The other reason, which I actually realized after I decided what I wanted to do, is that the glow in the dark pigments are still pigmented in the light. I could definitely try to create a pattern of toys that would all glow the same color to create a monster in the dark, but it would still be visible because all the toys forming the monster would have to be similarly colored. I actually works better to have the smaller object (in this case, the teddy bear) glowing, because then I can remove the monster completely in the darkness.
Alright, you persuaded me 😉 I just wanted to make sure you had a well thought out intention for this decision.
Love the teddy bear being a part of the monster. And I agree that it might be more interesting for the monster(s) to appear the dark instead of the toys.