Original sentence: In Boom Town he openly flirted with the Doctor in front of Mickey, and the Doctor played along.In The Parting of the Ways Jack in fact kisses the Doctor — although the actual kiss was obscured by the camera angle.It became apparent that Jack was (at least) bisexual, an orientation which the Doctor pointed out was more common by the 51st century, when mankind dealt with multiple alien species and thus sexuality became more flexible
Edited sentence: In Boom Town he jokingly flirted with the Doctor in front of Mickey, and the Doctor played along.In The Parting of the Ways Jack in fact kisses the Doctor — although it was only as a display of his excited happiness over the new plan to be implemented agains the Daleks (he kissed Rose as well).It became apparent that Jack was (at least) bisexual, an orientation which the Doctor pointed out was more common in the 51st century, when mankind dealt with multiple alien species, and sexuality was forced to become more flexible to facilitate relations outside the traditional human biological sphere