Re: "Right Nor Wrong"
Thank you for this detailed response and also for your journal rec; I'm glad the relationship and backstory worked for you. I love Snape/McG, but I realize that they might not automatically occur to readers as an obvious couple /g/.
Squib might have some low level of magic within them
I find the whole concept of Squibs to be interesting, and I've found it fun to speculate about them, about how they would or wouldn't find a place in the magical world. And you're right -- a lot of poor Filch's sense of his own "magic" could just be his wishful thinking.