cool is complicated (and means different things to different generations) : cachet (friendliness, caring, attractiveness, personal competence, drive for success)  vs contrarian (rebellion, irony, toughness, hedonism, thrill-seeking) in journal of individual differences

“If you perceive a peer as rebellious, ironic, rough, etc., then you perceive him or her as cool (by the old-time definition); and if you perceive him or her as cool (a positively valenced word), then you (by the halo effect) perceive him or her as friendly, competent, generous, etc. Thus, the halo effect might win out over the semantic tension between cachet and contrarian traits when judging the coolness of actual people.”

the new york times reports on how to make the most out of having ants in your pants

the atlantic reports on the positive correlation between embarrassment and likeability

“But the 19th baby was different. She was distressed by novelty — new sounds, new voices, new toys, new smells — and showed it by flailing her legs, arching her back and crying. Here was what Kagan was looking for but was not sure he would find: a baby who essentially fell apart when exposed to anything new.”

Anxiety and Temperament in the New York Times

Spheres (by Anka Zhuravleva)