Marzipan made their first appearance in the episode Blue Hour, where they were seen interacting with Nico in the early morning. It is heavily implied that they were thinking of committing suicide.
Through the Strawberry Mug, they were warped into the void, realm of AMM. Marzipan could not survive there, so AMM transported them to the planet Brinna, under the assumption that Gravity could help them. Marzipan was corrupted in the process.