Though Luna did not seem to get along with Michelle much as kids, they seem to be friendly enough that Luna cared about her well-being in their ten years of separation. Michelle also helps Luna out against the Wild Boar at the beginning of the story, and provided that Luna shares information in their first meeting at the top of Kentz Mountain, will give her a Kreytes Leaf in return.
However, Michelle ends up betraying Luna after being captured by Berto and his warriors (she attempted to warn Luna, but Luna fails to notice the hint), which leaves a scar on Luna's heart for a majority of the rest of the game. After the game's end, when Michelle asks to stay in Luna's old house, Luna forces Michelle to clean the house and do laundry as retribution, knowing that Michelle hates it.
Although their initial meeting began with a fight, the two eventually became good friends. Though Luna was wary of making friends after Michelle and Robin's betrayals, Pieberry's straightforward, sincere attitude wins her over.
Luna's first encounter with Justice is at Aimhard's Temple, when she realizes that there is fighting taking place behind her; Justice and Pieberry are fighting, and when Pieberry gets knocked down, Luna decides to assist her. The two don't encounter each other as much as Pieberry and Justice do, Luna rescues him from the Demon Kate and he leaves behind his tainted sword as a gesture of thanks. Luna also watches his relationship with Pieberry develop, witnessing them fall off the cliff together and later coming across Pieberry sleeping in Justice's lap.
Ludina is Luna's true mother who was forced to abandon her because of her mistake in the past. She gave Luna to Aramute trusting him to raise her into a proper deity unlike herself. After completing Ludina's side quest, Luna figures out the truth on her own, and tells Ludina that she forgives her. In the battle against Jude, Ludina will appear with Aeris to buy time for the villagers to escape, she also claims that Jude used to be in love with her in their conversation.