@cor3zone Nagatoro is dysfunctional, but it's obvious that without her pushing and cajoling him, senpai would remain the useless pussy forever. She is nasty, but her motive starts to shift into something much more positive lately, shown by her standing up for senpai and trying to make him do the best he can in everything. The rest of her gang are just bullies though.
President is just eccentric. We don't know enough about her to really say much.