The composite Sun in the 8th house shows a private couple behind closed doors and with deeper depths at work than what appears on the face of the relationship. Survival issues are powerful themes, and they might have to go through something pretty tough together. This house rules all sorts of things: debt, abuse, death, manipulation, and power struggles, etc. The emotional turmoil created by these kinds of situations can create a deeper closeness in the relationship or crises could rip the couple apart if the pressure becomes too much. Any difficulties in the bond must at some point be laid out on the table and talked through honestly before the relationship can properly grow.

Astrologer Liz Greene says that an 8th or 12th house type of composite chart could be involved in a relationship that is secret. The reasons for a secretive relationship could vary according to each situation. Perhaps, it is due to racial, religious or social class or even something else deeper at work. It could even be due to an affair with someone who is already in a steady committed relationship. Like Romeo and Juliet, an 8th house composite couple may have to keep much of their partnership underground. Betrayal is another issue that could enter into the picture along with the fear of abandonment, jealousy, and possessiveness. Taboo issues could come forth, because generally this placement is a hotbed of intensity. Yet, quite often, an 8th house composite Sun will work subtly and is not always evident on the surface.  

Positively, some couples with this placement may share an interest in the mysteries of life together, or share a business or some other kind of  partnership. Whatever the case, honesty is a good thing and they can build a relationship of true emotional depths, but sometimes knowing all their feelings, past events, and inner-most thoughts could prove too much. Ultimately, a lot of struggle could be avoided if both partners are prepared from the start. With this composite Sun in the 8th house of the chart, the relationship can evolve to the highest transformational level or become a source of trouble in their lives. 

Enter the eighth house composite Sun: the soul-nakedness is the essence of the process these two have triggered between themselves. They’ll pay a price in terms of psychological effort, humility, and sheer emotional exhaustion sometimes. And they’ll get what they pay for in intensity, sustainable passion, true closeness, and a sense of having hit the bottom on evolutionary warp drive. Skymates 2