I had a Bichomo about two years ago for maybe two months. He was very aggressive towards other people and towards any male. He warmed up to me after a couple of hours of trying to get him out of hi cage. He kept lunging at us he was that afraid. It took him a good two weeks before warming to my father and brother. When he was outside and any one was walking by he would run full speed towards that person with his teeth bared and growling. He never showed any aggression towards me. He absolutely loved taking off leash walks although I only took them early in the morning and when it was dark because I was afraid he would bite someone. He did bite several people including my sister. The reason I think is behind his behaviour was because he came from a puppy mill and I think he never fully forgot his experience. He was a bag of bones and dirt when we got him and trusted no one. In the end his behavioural issues where too much so we had to sell him but he nipped the potential buyer and they decided he wasn't for them. We had to let him go in the end because he was too far gone. We at least gave him a few months of what it is like to know a loving touch and living like a dog should live.