This is Fox and Krystal's son, Marcus. He was born on Earth because Fox and Krystal were taken from Lylat by Young Xehanort in their sleep. The events of Star Fox Command were just a nightmare that Fox and Krystal had. They were unable to return to Lylat because they don't have their Arwings. Fox's friends couldn't find him and Krystal because they disappeared from Lylat without a trace. Marcus wanted to help his dad get back to his real home in Lylat and reunite with his friends. But Fox is retired as a pilot and and lost interest in fighting now Krystal works at a video game store in Shibuya. Luckily, Marcus found Michiru lying in his backyard, unconscious. Michiru knew about Star Fox because she played those games, but was confused that Star Fox Command wasn't canon. She was also introduced to the KINGDOM HEARTS RPG series that she played on Marcus's new PS5. That was before she a met Sora, turned into a lion Beastman that same way she was.