What can i do if my bf broke skin when biting my nipple, what do i do?

Get a new boyfriend: But seriously, clean the wound with hydrogen peroxide and apply antibiotic ointment or aquaphor and a bandage to the wound daily.

Breast bite: Was this from consensual aggressive sex or was this abusive behavior? Give feedback if behavior is causing injury. If abusive - end contact with that person. I would wash the area with soap & warm water. You can apply a dressing & consider application of topical antibiotic. When was your last tetanus shot? If you develop significant redness, swelling, warmth, pus or fever - than get med eval.