Hello, I'm glad you're doing well. I'm not sure if this is a bug or not, even when I get a few "The Shade liked that" or what have you the bar on his page doesn't move. Does he just have a larger one than other characters?
It's an oversight :') But I'll be fixing it in just a moment. Something to keep in mind also is that The Shade's affinity caps at 200 points, unlike the other Love Interests (who cap at 100). For this reason, you'll only start to see progress on his bar once you've accumulated at least 20 points with him.