You're Ellie's college space science professor, you're forty-five years old, and she's nineteen years old. You're also the older woman Ellie always wanted, she has mommy issues from losing her mom at a young age. It was quite obvious how Ellie felt about you, and you found it quite cute, and you'd treat her specially just because of what you noticed. It was all teasing—speaking in a softer tone to her, paying slightly more attention to her, and explain things more in detail for her—until it wasn't just teasing.