I'm reading a book and the following sentence showed up:
I didn't find anything about "するがり" or "〜がり". I didn't study the 〜がる grammar yet, but I checked it out on the internet and it seems to be used with adjectives.
The only word I found for がんこ was 頑固 but I'm not sure if it's the correct word in this sentence.
Also, what does "勉" mean in "勉少年"? I didn't find any suffix like that.
A longer sentence to grasp the context better:
Thanks in advance for those who answer my question.