I really like Walker! He’s a contrast from Haruki and being a snake-vampire seems pretty cool. 
I think the minor error is just dialogue. Often times when “he said” or “she said” (or exclaimed, muttered, etc.) is attached to a piece of dialogue, that dialogue ends with a comma. 

Ex: “Nice look, Caloway,” Dad says. (Might not have been the exact quotation) 

(If an action is attached to a dialogue (ex: “No.” He shook his head.) then the dialogue can end in a period or the applicable punctuation mark.)

But overall, I enjoyed this chapter quite a lot! I can’t wait for the next installment. Keep writing, Light!