Moshi means smoke in swahili 

little moshi was small as a cub but grew much larger as an adult,  he is the young litter mate of upendi, and son of kiara and kovu, 

the older moshi got the more cunning he became, much to his name sake, he operates from behind the curtain and offereing help while remaining pavifistic. though he himself does not want to rule, he eventually becomes upendi's advisor when she becomes queen of the pridelands, 

he acts as upendis guard and takes excellent care of her because she is his darling baby sister, Moshi is the second youngest while upendi is the youngest, 

moshi strives to blend in and while strong his fighting power comes from his stealth

motto "Yes Upendi, why would i want to rule the pridelands? i am content protecting you and my family , that is all."

"You hurt her, and i swear to mufasa, i will hunt you down and rip you apart."

When moshi and upendi were cubs , upendi fell into a stream and moshi went in to save her even though he himself could not swim, 

his eyes are green like kovu's

NOT INCEST  moshi and upendi just have a very close relationship, since their parents were busy dealing with the war their older siblings started, upendi and moshi were often left alone so moshi developed into a father figure for his emotionally weak twin