Sorry this is out of topic. Is Mimi means cat in chinese? Usually sphynx cat in Egypt monu...

mao = cat in Chinese

According to some person on the internet:

1. The problem of the Chinese language is that word meanings are closely associated with the writings (think about hieroglyphs), but the written language is not a form of record of pronunciations. In other words, the pronunciation of a Chinese word has little association with its actual meaning. Apparently, whatever "mimi" means in Chinese, it is not written in Latin alphabet. Without the Chinese writing or context, there is usually no way to tell its actual meaning


2. Since Chinese is a tonal language, it is highly recommended to include tone marks or numbers while writing pinyin. In Simplified Chinese, the five tones for “i” are: ī/i1, í/i2, ǐ/i3, ì/i4, i/i5.
mīmi(咪咪) means tities or a cat onomatopoeia
mímí(迷迷) means seductive, lustful, or hypnotized
mīmī(眯眯) means squinted, sometimes interchangeable with 迷迷
mìmì(秘密) means a secret
mǐmǐ(靡靡) means titillating or decadent
mìmì(密密) means overcrowded or contiguous

Now I also got curious and went and searched last chapter raw and found that his name is written like this -> 墨赫弥斯 which seems to be written in pinyin like "Mòhèmísī"

Given the previous reply, its probably just a nickname created by repeating one of the characters in his name. Many children's nicknames is just some character of their name repeated (or some other meaningful character, e.g. zodiac)