I’m not a guy, but I do have a husband and I hope I can help you❤️!
I think it’s quite realistic for a man to feel insecure, men might just feel it about different things than women, or act upon it in different ways.
Maybe Alastor feels that Kit attacks an insecurity of his? Is Alastor desperately hoping to impress someone and tries and fails, but Kit does it effortlessly?
What is Alastor insecure about? And how does Kit bring that insecurity to the surface?
(An example of a guy with insecurity) In Harry Potter, Draco Malfoy bullies Harry constantly. Part of this is because Harry, by being essentially the chosen one and who does not tolerate Draco’s bullying and refusing to be under his control, attacks Draco’s power over other students. I haven’t done an in-depth analysis of Draco’s personality, but he is clearly insecure about his power, and desires to dominate, probably as a way of earning his father’s respect/approval, adding to his motivation to exercise any amount of power he can over Harry at any opportunity.
Also, I know this is unrelated, but there are three things that are the most stressful to a guy: Getting Married, Moving, and a New Job. I don’t know if this’ll help you, but I learned it in pre-marital counseling and I thought it would be a cool fact to help you out.
We crazy people are the normal ones.