There are actually five chambers of the heart. The fifth one holds all your loneliness, which for some people stays put and for some people leaks out slowly. 

There are only five unique locks and five unique keys. You could enter every fifth house, open every fifth safe. Every fifth person you see can take everything you have.

There are five dead astronauts buried on the Moon. The Moon does not know what to do. They lie in complete silence. The Earth longs for their bodies. 

Everyone gets five true loves and five enemies. If you don’t use them up they all arrive near the very end, some of them cursing you and and some cursing back, defending your every action.

There were originally five Gods but only one showed up. God waited, unsure, then got started. Right away God knew it was too much, that the work would never end. Where could they be, God still wonders sometimes, looking over their shoulder.