This is basically saying that he hopes in every morning of farewell, he wants her to personally tie his tie, which is a proposal!
Even if Xia Siyu initially had a straightforward mindset and couldn't GET that he was actually flirting with her. But when Bo Yan reached out to hold her hand and tie the tie together, her thoughts instantly returned to that morning when Bo Yan misunderstood her, the buy-one-get-one-free morning.
Although that morning, Bo Yan misunderstood Xia Siyu specially choosing a Valentine's gift for him. Xia Siyu, due to lack of sleep, did not respond to his "wishful thinking" either. However, at this moment, it seems like the scene is replicated, and her heart is filled with memories. Fortunately, the memories, although a bit of a mistake, are warm enough. Especially, there's him.
But Xia Siyu is not the type to blush and lower her head, not knowing how to respond when hearing a man's confession. She intentionally said, "Can't you do your own things yourself?"
