Your Ascendant signs are very incompatible. Your Moons are conjunct even tho out of sign. Perhaps that's where the attraction comes from. I'm a Cappie woman and dated a Saggie for 1.5 years and it was horrible haha. Even though his Ascendant was conjunct my Dsc, and our moons were in opposition and all this "great" synastry, there was just major incompatibility.
So yeah your Sun also squares his Moon which is not a pleasant aspect. Your cool and collected and grounding self and Capricorn sun is cooling down his fiery and explosive emotions, Aries Moon, since this is the most exact aspect, it is the leading one in the whole Synastry. This is where the main attraction comes from.
Also your Venus sextiles his Moon which is again a pleasant aspect. It's a supportive aspect that can ease the tension from the Sun-Moon square. There is something about him dealing with his own anima, recognizing his own animus inside of you, so this causes some conflict, as there is a subtle reverse of roles.
I ran a quick synastry for you.
Mars conj Mars - In this relationship, two individual egos try to go in the same direction. There may be competition, but it would be directed towards a common goal. The woman identifies herself with her animus in order to keep up with her partner. In doing so, she loses some of her femininity in some sort of "brotherly" competition. They push each other to generate maximum energy. Sexual expression may be limited because they constantly challenge each other. This aspect can be disappointing or it can stimulate significant achievements for both partners.
Sun square Moon - his aspect causes difficulties in perception and understanding. These people often misunderstand each other´s feelings, perspectives and principles because they both have to face internal struggle associated with sexual expression. The woman may doubt her femininity and the man his masculinity. These personal problems will affect the relationship by blocking more important aspirations while each partner is busy overcoming the problem by reshuffling their male and female roles.
your Asc conj his Mars - This combination is more gentle than conjunction. People share the same interests and enjoys many activities together, work situations included. They are able to fill mutual needs and cooperate well, it's good for marital relationships. The couple may help each other grow both physically and mentally. The Ascendant person may feel a boost of energy by being in the presence of the Mars person.
your Moon trine his Mars - The natural maternal instinct of the woman connects with the wishes of her partner while he leads her forward into the future. Their attraction is instinctive and easy to manage. The woman learns how to turn her instincts into actions, while the man learns how to act through instincts. They work together and discover new things about themselves and about the world around them. However, if this relationship is to survive, they both need to curb their sometimes restless or even reckless attitude.
your Moon sextiles his Venus - This is an excellent aspect for good compatibility. The woman feels emotionally comfortable, and her partner enjoys her support and mothering qualities. Both partners are very creative. As a result, there is a steady stream of feelings, intuition and cooperation that never ceases to strengthen the harmony of this relationship.
your Venus sextile his Moon - This aspect suggests a happy relationship. The relationship is rather female-oriented and both partners are receptive and sensitive. The man wants to satisfy his needs. The woman is able to love him the way his mother did when he was a child. Thus, the love he gets from his partner is well known to his subconscious mind.
Your Venus sextile his Asc - This aspect is similar to conjunction and produces keenness and sexual attraction. Friendships and acquaintances may result from this aspect. People feel excited in mutual presence and they may often have friends in common.
your Sun conj his Mercury - This aspect creates a relationship in which the woman is very dominant. The man may feel threatened because he is afraid to be brought down to the role of a child. He can learn a lot from the woman because she appreciates him not for his sexuality but for his mental potential. She will encourage him with warmth and optimism, and this will help developing his mind.
your Sun opp. his Jupiter - This aspect adds to the relationship an element of fortuity and destroys the sense of reliability. Although both partners maintain a sense of individual freedom, a woman often provides protection to both. Lack of communication and understanding makes two life styles pull in opposite directions. If this relationship is going to work, each partner must eventually reassess his/her principles and philosophy.
your Moon square his Merc - This aspect causes tension between the natural maternal instinct of the women and man's ability to establish contact with her. Barriers in communication that impede the flow of the relationship are likely. The woman does not feel masculine "power" that she is looking for and she may become withdrawn or even stop communicating if she subconsciously feels some kind of threat to her femininity.
your Mars conj his Pluto - It is an intense and passionate relationship in which the woman abandons her traditional role and identifies with her animus. She helps the man find new ways to activate his subconscious mind. Thus, she becomes his driving force. She will help him gain power, which will eventually revive them both. When his dormant potential revives, problems may occur, but the final result will be a very dynamic growth.
your Sun conj his Uranus - In this relationship, the woman, who is trying to be herself, must confront the man, who is trying to change her. She is attracted by his unconventional manners. When his power and her will are connected, a sense of direction will appear because they are both in need of a common goal. Without it, the relationship will be lively but short-lived, and it will resemble the short fireworks on Independence Day.
your Moon square his Uranus - In this relationship, the woman experiences emotional disappointment because the man counts on her reliability and protection but tries to stay free of emotional dependency. He sees her as a symbol of his mother and sees the relationship as a challenge that he must overcome in order to defend his individuality during his struggle aimed at cutting the imaginary unbiblical cord with his mother. She finds him exciting, challenging and unique, but she cannot truly call him her own because part of his appeal comes from fantasies that constantly release him from emotional traps. This is an aspect that makes forming a strong and lasting relationship very difficult.
his Moon square your Uranus - The man is very possessive because he is subconsciously jealous of her "fancy women's position" and he is emotionally insecure. He feels threatened by the universal feeling of freedom expressed by his partner. The man may wonder why he does not agree with her more liberal views. In fact, she tries to free herself from her mother and rebels against her partner while he expects her maternal care. This is a bad aspect for a long-term relationship.
Basically the overall theme is that you got hooked up on a non-commital guy because part of you wants to change him and lead him in a better direction, while he rebels. He most prolly has mommy issues, or his mother was a free spirit and taught him to be one too.
The composite is not perfect, it has some potential, but with Sun conj Uranus it will either be an unstable relationship or an unconventional one. However this much depends on both people. This is if he wishes to commit which is entirely up to him, in which case you must be very allowing an non suffocating.
I'd say have fun see where it goes, but don't put much hopes or expectations on it. You might be pleasantly surprised. If not , at least you won't be disappointed.