1) can be used as a substitute for "little bitch";
2) expression of excitement;
3) when referred to a person you love/like despite some odds.
1) He did not use blinkers! What a gunny!
2) Oh, gunny! I cannot believe Ben asked me out!
3) I have been waiting for hours for you to show up. You are a gunny, Abigail, but I still love you!
Gunny is an amazing and perfect human being. Everyone loves Gunny because she is so modest and caring about you. For example, Gunny will tell you that you’re perfect, but that’s just her being nice, she is actually the perfect one.