[Oh. Porthos has given him that look enough times by now for it to be very recognisable, yes. Sebastian only looks mildly surprised for a moment before smiling up at him.]
Certainly I could, [really, people need only ask and he'll give his earnings away] but in this place there is seldom anyone wanting for such things, and for lack of a person to gift them to... [why not be charitable towards animals, right?]
You are newly arrived, I see. [so to speak] If you have not eaten yet since coming here, please help yourself. [Makes an inviting gesture to his basket of fish.]
These haven't been touched by the cats. [Why on Earth anyone would mind cats touching their food is beyond Sebastian, but apparently it's a thing...]