What is Hayama Akira's ethnicity supposed to be? Judging from the flashback in episode 23, where Shiomi Jun meets a young Hayama in a spice market somewhere, I get the sense that Hayama was probably not born in Japan.

And given that Hayama is 


Brown
A master of curries
Apparently a fan of tulsi


I have a sneaking suspicion that he's supposed to be some kind of South Asian. 

Am I right? What's his ethnicity supposed to be?
As someone who is from Tamil Nadu, I'd say it's very evident that he really is from South India. Was extremely surprised to see Kozhi Varutha Curry as one of his dishes because it's a purely Tamil-based dish. 
Even in one of the pages in the manga where they show him living in the slums, I could see a board at the edge of the panel that had Tamil writing, I think it's enough proof.