somewhere in the gospels, the sadducees or the pharisees (cant remember which) ask Jesus what will happen to men who have been married to more than one woman over the course of their lives (widowers I mean) once they reach heaven and Jesus makes it quite clear that in heaven there wont be relationships in that way and that we will all 'be like the angels'. no bls in heaven then. (or perhaps everyone is bl in the purest sense!)
If you mean 'the Kingdom of God' in a present sense (here and now) it gets a little more difficult. The problem is that we only have 'signs' of this Kingdom in our lives so we have to follow our own consciences much more.
There is one point I would make about what the Old Testament calls 'eunuchs'. I have often come across references in the Prophets (Isaiah and Jeremiah I think (I'm terrible with biblical references sorry!) make it clear how much God loves the eunuchs. This has always puzzled me but couldn't it be an indication that any hard and fast rules about all of this (such as in Leviticus and Paul) are far more human than divine?