ya, i agree with canncialman02 that brown snakes fit everything you are asking, but if you look at a mexican rosy boa, you will fall in love with one of those, i did, lol, and i dont even have one. but if i was to pick between the two, i would pick a rosy since not only are they beautiful, but you will be able to actually observe them more since they are bigger. and a lot of times i just hang out with my king watching tv for like half an hour, and she relaxes for me, but with northern brown, they are probly going to be crawling all over. but i have not owned browns or rosys, so i might not be perfectly right. also, i heard that boas are sensitive if you touch the top of their backs and they dont know you are there, is this true?
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i have one Brooks Kingsnake, hopefully breeding in the next couple of years! yaaahhhh, only if i can find a male though lol, but im still looking for a male lol