You shouldn't hold up manga because it disrupts the normal distribution process. Publishers have schedules to keep, and holding them up messes with that. Also, it could potentially lead to legal issues.
In some manga, a boy and girl friendship can hold up. It often depends on how the authors handle the relationship, the common interests or goals of the characters, and the way they support each other through various situations.
It could have a deeper meaning. Maybe it shows a connection or a turning point in the relationship of the characters. Different mangas might interpret it differently though.