These two powerful planets know what they want and are not afraid to go after it. When the urge is mutual this can be one of the most "intense and aggressive sexual aspects" found in synastry.
The square and the opposition between Mars and Pluto, although add tremendous sexual attraction, if not handled appropriately, it can be disasterous. If you have this aspect with your Partner and you see the competitive, or antagonistic side begins to show it's face, then don't think it will get any better over time, because it most likely won't but instead will escalate to the point of anger, deep resentments even in worst case hate. There is a fine line between love and hate, and this is Pluto's domain, you can pretty much say it about all hard aspects made with Pluto.
On one hand, this aspect often shows up between two strong headed individuals, that tend to disagree on practically everything, Or they are both pretty much set on doing things there way, Or one tries to control the other and this is how everything can go downhill and quite fast. If this is the case, you can expect power struggles, drama and in the worse case, violence. So, special precautions need to be made, just learn compromise.
The attraction although very strong initially can be broken down over time, if you choose to compete and push each other, rather than work as a team.
Pluto and Mars are two very powerful and aggressive planets, Mars more directly and Pluto subtly at times and explosive at others. If handled wisely and with awareness this aspect can be great for stimulating one another and adding strong sexual desires.
Both individuals tend to have strong desires, and they respect each other's internal strength, but at the same time, can be jealous of each other, competitive or just not willing to make the necessary concessions it takes to have a mutually satisfying relationship. It is also seen that one may have to be right all the time, try to dominate or even control the other.
When one pushes and the other doesn't give in, a battle of wills is likely, leading to many dramatic arguments. Ideally with this aspect it is best if you have some other softer aspects to help smooth the energy.
If there are other harmonious aspects (especially with Venus Moon, or Venus Sun) and both parties are mature enough to realize that stubborness, willfulness, competition or always having to be right, unfortunatly do not work in a "love relationship" and choose instead, to direct the intense energy towards mutual goals and sexual satisfaction. If so,then this aspect can keep the sex life, hot and busy for a very long time.
This aspect is considered to be a sign of possible violence or abuse. However, it most certainly is not always so. You do need to take both of the individual charts into consideration to check for any signs of violence in either one natally. If both people are not violent to begin with, then this will not likely be the case.
If the attraction is mutual and both people are mature then this aspect adds tremendous sexual attraction, but you do need to exercise caution and watch for being too aggressive with one another, because of the strong urges and the intensity you can easily inadvertently end up hurting each other or biting too deep, leaving war wounds behind.
In it's positive there are few other aspects like this that can drive the primal sexual urges "over the top" like this one. This is the purest form of "animalistic sexual energy".
Although, this aspect alone is not enough to keep two people together in a loving relationship, it will be a factor in couples that stay together, or going back even just for a strictly "sexual one".
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