I just don’t fucking get it. (Longish rant)

So I really don’t understand, so let’s start from the beginning my moms boyfriends son is almost 20 years old. He’s had one job ever and that was working at a movie theater, well that didn’t last long because he quite before they could fire him because he couldn’t get up for work in time. Keep in mind work for him started at 3 in the afternoon!! So he came over Saturday because well he wanted to see his dad fine whatever. (My fiancé and I live with my mom and her boyfriend for now we both now have jobs but for a couple months he was supporting both of us) so Wednesday my moms boyfriends son had a opportunity to earn some money for my fiancé’s boss under the table work at his house. They didn’t go there till 2 in the afternoon and he couldn’t get up and no one could wake him up. Trust me we tried not very hard but we tried he even flat out said,”I don’t think I should go today because I didn’t get much sleep.” He stayed up until past 6am, today again had the opportunity they told him when to be up and be ready by which was 12pm. Again he stayed up until past 5am at least actually past that because he came outside to my mom and her boyfriend with a cup of coffee. He blamed my moms boyfriends brother for him not sleeping even though his brother showed up at 5am so I call bullshit. On top of all of this he’s stolen weed from my fiancé and when my fiancé talked to my moms boyfriend about he said “maybe you gave him more then you thought.” Which is false because my fiancé uses it for his back and he pays with it with the money he earned. He’s almost out in three days three fucking days when that amount would have easily lasted him and my moms boyfriend two weeks. My fiancé has stuck his neck out twice for this kid and he hasn’t made any effort to get up in he afternoon, I finally told my fiancé to say his boss said no he already got two chances I’m done. He didn’t shower for 5 days maybe 6. He has like one pair of clothes he hasn’t washed. I want him gone or I want to leave but apartments are expensive here and we don’t make enough to save for one within a few months not counting furniture and stuff. I don’t get it all he does is sleep, eat, and smoke weed. Oh and I almost forgot he ate all of my fiancé’s chips without asking. (He didn’t put them in our room because they are normally fine out there) like my fiancé got two handfuls out of the bags.

Edit: my fiancé and I live here he does not live here. Last night my moms boyfriend was giving his son my fiancé’s beer because it’s “house beer”