[Niknaizorai]

If he is willing to sacrifice his life for a relationship with no babies, then its fine. One can do whatever one wants with his or her own life.

These relationships are not bad themselves. There must be a physical and also an intellectual attraction. Some Japanese women are very attractive even when they are in the 40s or 50s. They have an unique charm.

If there is not an intellectual attraction, it will not work out in the long term. I have seen couples of old man with very young woman. Usually, he is an important writer or intellectual or movie director. There is a common professional interest. So, she takes care of him while she satisfies her intellectual interests. It is a very enriching experience. Intellectual drive must be over the sex drive in this relationship.

Being a normal couple, the relationship will be temporary. A point in time where your souls meet for certain purpose. If he is a normal man, he will be happy with you but a bit sad inside sometimes because he will notice younger ladies and thats a cost for him. He has to give up the idea of having children. Youth is extremely precious and he deserves a chance.
If he comes from poor family then he might be expecting a change of status. He might not even care about not having children as long as he has a chance to get out of his personal circumstances.

Just be natural, both of you, and nature will show you the way.