It is noted by Izuku Midoriya that Melissa highly respects her father, seeing as how she wants to become like him: someone who indirectly saves people by helping heroes with support items. Upon learning about how David helps All Might save people with his inventions, she becomes inspired by this and tries her best to become a support engineer herself. Her love for her father is also shown when she tries to save him and when she instantly forgives him, even after learning that he was the one who planned the villains' attack.
Melissa first met All Might when she was a child and came to pick up a new costume from her father, and seeing how it protected him and hearing how her father was a hero to All Might inspired her to become a support engineer. Later on, she becomes familiar with All Might enough to refer to him as "Uncle Might" when she invites him over to I-Island in email.
Shortly after his arrival on I-Island, Melissa was quick to take note of Izuku's appearance, describing aspects such as his hero costume and the scars on his hand, leaving Izuku embarrassed. She later toured him around the I-Island Expo at the request of her father, and the two quickly bonded over their similar interests in heroes and support tech. After observing Izuku's performance in the faux villain course, Melissa gave him the Full Gauntlet in order to help handle his usage of One For All. She also revealed to Izuku that she is Quirkless, and that she shares a goal similar to him in wanting to save people's lives, indicating she considers him a good friend by that point. They worked together in trying to save the island and she tried to defend him from a villain but was knocked aside though seeing her hurt caused Izuku to punch the villain away.