Formal:
* "After years of feeling isolated, I finally found a fellow soul who understood my passion for astronomy."
* "In the depths of despair, she found solace in the presence of a fellow soul who had experienced similar hardship."
Informal:
* "We were both struggling with the same problem, so we just had to help each other out, you know? Fellow souls gotta stick together."
* "At the concert, I saw a fellow soul wearing the same band t-shirt - instantly knew we'd be friends."
Figurative:
* "He was an artist, a fellow soul who saw the beauty in the everyday world."
* "My dog is my fellow soul, the only one who truly understands me."
Note: "Fellow soul" often implies a shared experience, understanding, or belief system. It emphasizes a sense of connection and common ground.