I have been learning and practice Toon shader for feel weeks. I basically watched every Toon shader tutorial video on Youtube to make the best effect in my brain. 
This is my work and the notes so far. I tried many many ways. This is the easiest and affected. When I watch the new TV show "what if...?" I was interested in the glow on the character's side. I tried different ways but doesn't work.
And anyone has any idea or helps. I will appreciate
You can do it like this - Because a toon shader is made with a ColorRamp set to a constant value with a set number of "steps", you can just use a second ColorRamp with only the brightest step. Multiply both with your Image Texture to transfer the darks from the shadows over your image, but run the "brightest only" mix through an Emission Shader. You can connect your "regular" texture/shadow mix to the Mix Shader without any shader (BSDF) in between, and it will work as unshaded (normal for toon). Then, just connect the Emission Shader to the other input. You may need to turn up the emission strength a bit. Don't forget to enable bloom ;)
If you want a different color (than your base image) for your "glow" section, add a Hue/Saturation/Value node on the Emission side:
