Severus Snape has always stood on one side of love and looked at the people on the other side.
This time, he stood on the other side of love and decided to take the outstretched hand.
When Harry was in first grade, the heroine was in fifth grade. The beginning of the timeline was when the heroine was in fifth grade, and the basilisk incident occurred in sixth grade.
When evil people fall in love, the heroine uses third-rate tactics, and both of them are morally flawed. Including but not limited to: teacher-student love, seduction, threats, slander, lack of teacher ethics, etc.
Intention: This time, he stood on the other side of love and decided to take the outstretched hand.