It’s not that you don’t like your SS, you dislike the way he acts and disrespects in your home. You took away all of his electronics, why didn’t your BF do that? Why are you the one parenting this child? Your BF has to address him with the porn and have SS do his own laundry. I wouldn’t touch his clothes with a 10 foot pole. You tell your BF what you found and instead of finding solutions he deflects and turns it around that you are accusing his son about molesting your daughters and dog. I mean really! If your BF wants to continue living with his head in the sand and not get this kid help that’s on him but I’d seriously reconsider your relationship with him and possibly seek therapy. If he refuses that and to address his sons problems you need to take your daughters & dogs and get the h@ll out of there ASAP.

None of this is healthy for you & your kids!

Your post is quite difficult to read with the sentence structure. There are no full stops and too many commas. 

It could be the way you bring the subject up with your partner. Rather than tell him what SS is doing, ask him did he know this ‘xx’ and what does your partner think of it. Telling him all this stuff SS does, it sound like you are always being critical (even through you are right in what you are saying). 

I would take a step back, refrain from parenting. Just remember ‘not my monkeys, not my circus’ (the best phrase I’ve found on this site). Don’t wash his shirts, he’s old enough to do his own.

If you are concerned don’t let SS be alone with animals in your home. If you do bring the subject up, keep your voice neutral. 

Yeah... this would be one where I wouldn't go quietly about it.

There is sexual curiosity and there is illegal activity. I wonder if it is illegal to have beatility porn- like child porn? I know those are two different things but maybe there is another way to go about this when approaching your SO. 

I would make sure your daughters have the ability to protect themselves- just in case. Take a womens self defense course together- no woman ever said... "geeee... I shouldn't know how to keep myself safe". 

hands if your other half doesn't start addressing the issues with this kid. This kid needs a hard fast wake up call with some continuous follow up. Can he get him into an intesive counselling? Some drug testing?

If he's a straight A student, the pot smoking wouldn't bother me that much.  Almost every adult I know smokes, and they are all upstanding citizens in every other aspect.

He's old enough to do his own laundry.  Wtf.  If SS doesn't do his own laundry, DH can do it.  Not you.

The stealing is a big problem.  Maybe that's where he's getting the money to buy pot.  What is he stealing?  My SD is a theif, and I keep my purse locked up in my car when I'm home.  Our bedroom door has a lock on it as well.  You have to lock things up.  And of course he should lose priviledges.

The bestiality thing is crazy.  That's not normal.  I knew a girl in HS that used to let her dog hump her leg.  I found out later she was putting peanut butter on herself and letting him lick it off.  Add the last two sentences together to think what else she might have been doing.  Of course you don't want your dogs aroud this weirdo!

Your husband yelled at you about your mild reaction to this crazy situation.  What a jerk.  I'd move out.

Your husband is hyper-defensive about this kid, and in turn sounds like a complete asshole. While looking at dog beastiality porn is not illegal, it is disturbing, as is porn of brother's f*cking step-sisters. This kid is out of control. If he is only using his ipad for really disturbing porn, why is he allowed to even have an ipad....? You can block specific websites on electronics. You can even set up parental controls based on key words- it won't let him look at websites that involve dogs, step-sisters, sex, etc. I would get that set up STAT. I would also be checking his electronics regularly to see what he is using them for, and make sure he knows you are checking.

I disagree with ipsofacto on the weed-smoking. You live in Nevada? I'm not sure if it's legal there, but if it's not, then it's not just about if weed is "innocent", or if he's getting straight A's. If it's illegal, he is just asking for trouble. What if he gets caught, either by the police or at school? It's no longer innocent weed smoking- now it's fines, jail time, or being expelled from school. Even if it is legal...maybe I wouldn't worry quite as much, but he's still only 15, and it's still illegal when you're 15. There is still plenty of trouble he can get into with it, especially if he starts driving and smokes when he drives. Bottom line, no good can come from it.

Your DH is another story. I would not be ok with this situation at all, and I would go so far as to tell my DH that if things did not change, I would be out. I've told my SO that, for lesser things. I don't believe in idle threats, so if you have a serious come-to-Jesus meeting with him about this and he still gets mad and defensive and does nothing, I would seriously reconsider this relationship. You have at LEAST 3 years left of this- that's a longgg time to deal with this crap.

Stepmom, untill BM signs away here rights and you Adopt him in court.  That being said,  your real problem is with your SO, not the kid.  Yes the SS is on his way to loser Ville, and with out mealth health perfessional help.  There is not much you can do..   But SO Turing the kid problem onto you. And going after you is the big time just shows that SO likes his head in the sand.  So he will not see in frount of him.  That kid must go back to BM.  You should not be going through this.  BM and BF screwed this kid up and they should unscrew him.  REMEMBER you can not do more then the birth parents do. 

sorry