What a long process it is to get to know each other, to know each other, to fall in love, to promise each other, and to stay together.
He is secretive and casual, making people feel reliable.
She is shrewd and steady, and her weakness makes her feel firm.
He and she have been in love for a long time, they have a special liking for each other, they bump into each other, they care about each other, life and death are uncertain, they have no choice but to stay together for the rest of their lives.
Apart from research, the heroine is not omnipotent, especially when it comes to love, she is definitely a novice.