His stellium in Pisces does make him a very sensitive person. He is easily influenced by others because his Sun/Moon/Mercury conjunction is in the 7th house. This can make him receptive to negative energy in his environment and within his relationships. Mercury conjuncts Sun/Moon can point to overthinking and anxiety, and in his case, it might be about his own emotions. Mercury in tight conjunction to Moon in Pisces can be an abstract thinker, but also very dreamy and not practical. This can make him an idealistic person and he can be disappointed by his unrealistic expectations, which can turn into depression. His Sun/Moon/Mercury conjunct his Jupiter and it can magnify his issues because of Jupiter's expansive nature. Jupiter can drown him in his watery Pisces emotions. The most important parts of his identity: ego (Sun), emotional nature (Moon), and intellect/mind (Mercury) are tied into this conflict. Mars in 7th house puts the person's drive and ambition towards relationship, but it is in Pisces so the energy can be dissolved (Neptune as ruler of Pisces)
I also noticed his Pluto conjuncts IC. There can be a lot of pain and transformation in regards to his family. His early childhood might wound him deeply, and he carries it with him into adulthood. Since he is a very receptive and sensitive person as mentioned above, this can affect him more so than with others. His stellium is squared by Pluto, making it more intense and deep. He can be obsessive about resolving his emotional issues but at the same time trapped by it. Since the square is the hardest energy to work with, he can feel a lot of frustration and tension within himself.
Saturn in the 8th can also indicate anxiety and depression, especially in the area of sex and intimacy. He may find it hard to be intimate with someone, but his stellium in 7th house craves one on one relationships. Saturn here can bring about fears and a need to be in control of everything. He is not someone who can just go with the flow and it can make his turmoil more difficult to be resolved since he doesn't like changes. This position can make one person very attached to his family history and pattern, so he might expect his life to follow his family dynamics. 8th house is the house of death, sex, other people's resources, and transformation. Having Saturn there can bring many challenges in those area. He may tend to hold onto things (e.g his family issues). But he has to be willing to accept changes in his life and let himself be transformed in order to heal himself emotionally.
His Saturn also squares his Venus in Capricorn (Saturn as ruler). This aspect can make one feel undeserving of love and have low self esteem. The ability to give and receive love is not free flowing and he can be very frustrated in close relationships, which is what he focuses on (stellium in 7th house). His Venus also conjuncts Neptune (ruler of 7th house), putting more emphasize on his need for relationships. On one hand, his Venus in Capricorn squares Saturn make him practical in love and find it hard to trust others, but his Pisces stellium and the conjunction to Neptune make him idealistic, which create contradictions. He can put the partner on a pedestal and want a soul to soul connection, but he can be very discouraged once he finds out that the person he thought was perfect has flaws like anyone else.
Thats all I've noticed so far. I'm still practicing so please give me feedbacks on my interpretations. hope this helps!