That was a horrible, horrible thing. Especially after reading The Pandora Principle, or the very similar DC comics' Saavik origin story.
About 80 years
after being teacher and pupil, and both without romantic partners in all that time in between, they decided it was... logical
to become partners rather than remain alone.
I know some human teachers and students who impatiently waited about five years till they thought that society might accept their decision.