benching
warning
the one-line answer
Keeping someone as a romantic backup while pursuing others.
Benching means keeping someone on the bench in case your first choice does not work out. You are not rejecting them but you are not choosing them either. They wait.
mainstream
Your coworker might use this word.
01 / in the wild
hear it move.
warning
he's been benching her for months while dating other people.
He is keeping her as a backup option while pursuing others.