I would say that he is selfish.
Jerry isn't grateful for that nickel the narrator gave him as he believes it is not enough given that everybody else gave more. He is acting rude and inconsiderate and doesn't think about the fact that the narrator may not have more money.
Haiku poems are easiest
You just need some <span>syllables
And poof thats a poem
(This is a haiku poem if you couldn't already tell)</span>
its basically the fact that they achieves a talent to red write and teach yourself who you are as magi did.