Heejae may be like 42 or whatever but he has some maturing to do. His relationship with music (and other people, or lack thereof) stunted his emotional growth so every time he acts like this, he feels more like a bratty teenager than a grown ass man. It's definitely part trauma response, but also ego. Garam's expression, that flash of anger, said it all. It's like beating a dead horse with Heejae, but Heejae thinks that it's Garam's fault for being upset and not Heejae's fault for being upsetting.
Heejae may be like 42 or whatever but he has some maturing to do. His relationship with music (and other people, or lack thereof) stunted his emotional growth so every time he acts like this, he feels more like a bratty teenager than a grown ass man. It's definitely part trauma response, but also ego. Garam's expression, that flash of anger, said it all. It's like beating a dead horse with Heejae, but Heejae thinks that it's Garam's fault for being upset and not Heejae's fault for being upsetting.