In a composite chart, what does it mean when the Pluto square personals planets (Sun, Moon and Venus) ?
The negative themes of those planets permeate the relationship and need deep conscious work to be resolved.
Sun: A lot of jealousy and egotistical behavior, one or both people needing to be the center of the other's universe, needing constant validation/attention or feeling the relationship is all about them. Possibly cheating.
Moon: Emotional problems likely on both sides that results in excessive neediness, misunderstandings or passive aggressiveness. The relationship makes both people withdrawn or reluctant to allow other people into their lives. Someone is encouraging emotional/psychological dependency in the other person.
Mercury: Miscommunications and secrets, one or both people being manipulative or trying to influence the other's way of thinking. A lot of harsh words exchanged during arguments or someone is being verbally abusive. Sado/masochistic psychological tendencies within the relationship.
Venus: Codependency issues, financial problems, a difference in core values. Difficulties relating or compromising. One partner controlling or dominating the relationship. One or both people projecting negative judgments onto the other. Cheating or paranoia regarding cheating plagues the relationship.
Mars: A battle of wills within the relationship. Constantly butting heads or arguing. Intense feelings of anger and even a desire for physical violence (though they may not act this out). Cheating or wanting to cheat can become the main source of frustration.