Grooming, the manga.
@JustCallMeApe she is basically breaking the biggest taboo as a teacher, so she really ought to distance herself for at least as long as they remain student/teacher.
It's worth noting that if they were to end up in a relationship, the student should be the one to initiate it since the imbalance in power means the teacher can coerce the student into a relationship. A possibility which sullies potential relationships, unless the "lower" party initiates things and they are no longer in a student/teacher relationship.
I might sound harsh, but this is actually giving them quite some leniency. Professors and teachers coercing their students into a sexual or romantic relationship is quite a bit g deal since it undermines the trust in the entire system, plus is quite gross. And because you can't remove the power dynamic from the equation, people might feel pressured to enter a relationship when asked. It's really difficult to disentangle the power dynamic.