Origami is a person that rarely openly talks with other people unless needed with only a few exceptions such as Shido Itsuka and Tohka Yatogami. She isn't a shy person, but more of an unsocial type of person.
She can be a bit reckless or aggressive if she has a goal or purpose to fulfill, she's also willing to do something someone else wouldn't to accomplish such goals as shown when she did everything Shido asked of her when he was trying to get her to not like him which shocked everyone around her.