A person who has a knack for defecating on a person's perky nipples. Possibly during intimacy.
A person who is such a huge bull shitter that it makes your nipples pop.
Last night, I found out Stacy's mom is a nipple shitter.
Wow, I couldn't believe what the diarrhea bullshit that was coming out of their mouth. John, you are the biggest granny nipple shitter of all time.