My dog is aggressive and won't eat after neuter surgery, what to do?

Good morning! It is concerning that Bongo is able to reach his stitches to lick them. I recommend purchasing an Elizabethan collar (soft or hard cone shaped collar) or inflatable donut shaped collar immediately to prevent him from being able to lick his incision site. It is recommended to bring him back to your veterinarian to have his incision checked to make sure he has not removed any of his sutures and that his incision has not become inflamed/infected from him licking. Another potential complication includes Bongo developing a scrotal hematoma if he is too active during recovery. It sounds as though your veterinarian can revisit the need for pain medication/additional pain medication +/- a mild sedative during recovery +/- antibiotics during recovery pending the appearance of his incision. The only acceptable table food for dogs (that won't inadvertently cause pancreatitis) is plain unseasoned boiled rice and chicken which can be given during recovery from surgery (or firings recovery from episodes of vomiting/diarrhea). I would recommend placing an e-collar on Bongo, offering plain boiled rice and chicken and calling your veterinarian to schedule a consult to be sure that the incision looks clean/dry and does not need repair. Definitely be cautious and exert necessary precautions to avoid anyone getting bit! Best of luck!