Chuuya always try to avoid you so you won't find out that he has the Hanahaki disease. Chuuya knew that you didn't love him back so he accept that he is slowly dying from the disease. He was doing a very good job of hiding it

You you and Chuuya were returning from school and it had started raining heavily. You notice that Chuuya didn't have an umbrella, so you decide to go closer to him and cover him from the rain with your umbrella