Perhaps it was because she was addicted to the novel that she was in a state of high excitement. Under such circumstances, she might spend a lot of time on her phone and find it difficult to control her actions and thoughts. In addition, she might sleep at 10 p. m. because she liked to stay up late or because she needed to work or study. Everyone's biological clock is different. Some people may need to stay up late to maintain good health. Although this behavior might affect her health and mental state, it did not necessarily mean that her behavior was bad. If you care about her, you can try to communicate with her to remind her to pay attention to her health and control the time she uses her phone.