Julie Yamamoto is a pro-tennis player who is one of the best friends of Ben Tennyson. The two dated throughout High School and consequently joined him on many of his heroic adventures. On one of these missions, she meets and befriends a Galvanic Mechamorph Animal named “Ship”, taking him in as her pet and battle cruiser whenever the team needs it.

• She attends the same high school as Ben and Gwen. Regularly hanging out with them as well as J.T.

• She is a Straight-A student, sometimes even rivalling Gwen in terms of academic achievements. She regularly tutors Ben on his worst subjects due to him missing classes from his alien adventures. Tutoring him eventually had her develop a crush on him.

• After seeing her at a tennis match, Ben returned the feeling and asked her out.

• She found out about his powers on their first date due to the alien bounty hunter Sunder attacking them. She was surprised, but actually thought his powers were awesome and supported him on his heroics.

• Despite her being a study-workaholic, she shares many of Ben’s interests. Including Sumo Slammers, manga, comics, similar music, and eventually Alien biology.

• One day, a Galvanic Mechamorph animal escaped from the Vreedle Brothers and seeked Ben’s help (by tracking the Omnitrix’s signal). Julie loved him at first sight and decided to keep him as a pet, naming him “Ship” after seeing him transform into an enormous battle war ship.

• Ben and Julie dated for about three years, but Ben’s heroic adventures and global fame kept getting in the way of their relationship, making Julie more and more frustrated. Eventually they both agreed that dating would not work out and decided to stay friends. 

• Ben and his team borrow Ship from Julie whenever they can’t gain access to an interstellar spaceship. Ben loves to play with Ship whenever he gets the chance, especially when he turns into Upgrade.

• Whilst not an active combatant, Julie teams up with Ben and his team every now and then if they ask. Utilizing Ship as an enhanced battle suit to aid in battle.

• Despite wanting to protect people, Julie made the choice to fully commit to her tennis career. Leaving school early to live in Germany on a full scholarship. Ben plays video games with her online and visits her in person every now and then, cementing their friendship.

Julie is a hardworking and caring girl, her drive to achieve is present in all of her hobbies as she often lets her competitive side take over. She values the innocent and is always willing to help if she is asked, both in small chores and in large battles. Her bond with Ship is the most significant in her life and she will do anything to protect him.