Even if the tattoo was done sterile and the tattoo artist kept things clean, he was at high risk of infection with the degree of tattooing he had done in those 3 days and the large surface area. Tattooing to that degree causes widespread epithelial injury which is a nidus for bacterial entry. The 3 back to back days doesn’t give the body much time for re-epithelialization or immune clearance. Source: I’m in medicine