If she were to start a reln with u while she's still attached,
that would constitute to cheating. And if there's conscience in
her, it would be a matter of time b4 e guilt consumes her. If u
really like her and have her interests at heart, u should only go
as far as expressing ur feelings for her. Until she ends her
present reln, as a respectable young man, u should not make further
advances.
Get it right from the start. Besides, I dun think u wan her to go
out with u on a date for a couple of hours only for her to rush to
meet her bf thereafter followed by a bonking session.