Mattin has a friend in Westcrown, they are almost the same person but with a slightly different accent. Every arena owner in Ostenso is direct competition and sometimes they send retired gladiators to attack each other; there can be no camaraderie there. But there's no competition with an arena in another city, so it's possible to just be friends and talk shop. 

This friend has a big house and is letting Mattin (and several servants and bodyguards) stay as guests. Mattin and his friend are currently touring the menagerie, which at this time is mostly kobolds.

"A toast to Kobolds, a legal gray area!"

"Yep, proclamation only mentioned humans, halflings, and orcs. Have you seen the rates these days, I can get twenty halflings for one kobold!?" 

"For all the good it does you, next week you'll have zero kobolds zero haflings." 

"You're lucky to have thousands of them here; much better than the sewers back in Ostenso, all we have are rats."