>>112987394She's an average teen girl teetering between mediocre and popular on the ladder of higschool hierarchy. She's not a bad person, but she isn't exactly very likeable either. She's emotionally fragile, vane, selfish and her caring about being popular in school while having the knowledge of how inconsequential something like that is on the grand scale of things makes absolutely no sense.
But then there's no objectionably likeable main characters in this show. So it's not like Summer stands out. Her storylines are somewhere in the middle as well.
So far, I hate how none of the characters really grew. Rick is still Rick, Morty is still a dumb kid who thinks with his dick, just more used to weird shit, Summer is still a selfish cunt, Beth is still in a midlife crisis, Jerry is still a dumbass who goes for what he perceives as momentary satisfaction over any long-term plans.