Abandon Shipping: The ending of J to X has all the three marionettes regress into a child and erased their memories, effectively demoting them from potential love interests to adopted daughters to Otaru.
Anvilicious: J to X had such a blatant antideforestation episode that most viewers already got the message in the first five minutes.
Big Lipped Alligator Moment: In J to X there is a flashback episode where while the Marionettes are remembering their origins, Bloodberry has a memory of her being berserker and gets dizzy. This is never brought up ever again.
Bait-and-Switch Lesbians: During her Heroic Sacrifice, she realizes that her love of the oceans came from her awakening underwater — meaning that her feelings for Lime were completely platonic, y'know?