But I will say the same what Niyarae said - "safi" as every arabic adjectives don't take agreement with nouns. In this case - Emilian ni safi. And if you have some proved informations, please, let us know. :)
Here is an example of someone who is decidedly not a language expert, just a Tanzanian man offering his views on why "being stylish begins with cleanliness". He uses both msafi and wasafi. Could we theorize that safi is an adjective, but msafi/wasafi has become a noun? Anyway: https://www.jamiiforums.com/threads/dondoo-za-kuwa-msafi-na-mtanashati.598255/
this is the second example describing a person as clean. Is there some Swahili understanding of this word other than "not dirty?"
Honest, unselfish, straightforward, genuine, true. I guess these are better translations when you talk about people.
It is also used colloquially in a similar way to the English word "cool," sometimes as a response to a greeting, etc.