Mimas thinks that Nysa tends to be pretty dense, but he finds her company pleasing because she radiates warmth. While the two are more like cousins, he treats the other lunaith as more of an older sister.
Nysa likes to tease Mimas because he is smaller than she is and tends to be quite shy, but she doesn't mean any harm. While the two are more like cousins, she treats the other lunaith as more of a younger brother.
Muti is the creator of Mimas. She created him as a way for Nin to always remember her and to also ensure he is never lonely since the two had to separate when they ascended. Her love for her sibling has imprinted on Mimas, shaping his personality in the process. She bestowed upon him the ability to use water/ice and his source of life and power springs from the moon since that is what Muti created him from. Her personal opinion is that he is very cute.
Mimas was created by Muti as a gift to Nin. Mimas is a spirit manifestation brought to life from the power of the moon and he has the ability of ice. Due to the purpose of his creation and the wish he was born from, Mimas has always had a level of respect and love for Nin. He was made to be more of a pet or friend and a memento for the deity so that he would never forget his sibling. He also serves a duel purpose as a guard, defending his master's temple palace.
Nin Kala finds Mimas endearing. Even though the little one can be somewhat clumsy, he feels that Mimas is someone that he can talk to that won't judge his opinions. While Nin Kala typically finds solace in voicing his thoughts to Cheleb, should the Guardian ever be forced to leave his side or have business to attend he knows that Mimas is there to listen as well. Mimas was his first companion, even before Cheleb since both he and Muti had made companions for each other right after their ascension.