First off, I get the attraction to girls who are unavailable. I myself seem to be attracted to women who play hard to get and generally have their own game they run. It is a challenge, and it makes things interesting.
Second, I think this is already in the bag. You've gotten her to cheat technically. I think you could turn it into full on sex under the right circumstances (your place as "colleagues", turn it into kissing, bite her neck, nibble on/breathe in her ear, then move into sex. Once you bang this girl she will eventually leave for you.
That said, if she cheated with you...And I don't condone stealing another mans girl. If a girl is taken, find a single one. Now if you would take a min to answer my question...
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