<human>: My SO [27M]'s best friend is kind of a scum bag. He is very different from my SO, but they get along very well. They have known each other since grade school, and he got my SO his previous job, so he's not a terrible friend apparently. However, he makes many shitty decisions. He's cheated on every single one of his girlfriends, drives drunk - with beer jugs sometimes in his lap on the driver's seat! - and has many stories that just reek of douchebaggery. He just generally looks like a mess and although he doesn't seem to have that much influence on my boyfriend's behavior, I'm afraid that could change.

My SO may be moving in with him in two months (they're looking for apartments right now). We see each other pretty much every day, but I wouldn't feel comfortable staying at a place where I'd have to be around his best friend constantly. They're not in a great place financially, and we live in a very expensive city; with only 1.5 months until my SO has to move out of his current place, this is an easy option.  We've only been together ~5 months, so I'm not sure what I can really do. It honestly scares me to think of what things will be like when his best friend is his housemate.

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<bot>: SO's best friend is an asshole and makes me uncomfortable. They may be moving in together. What do I do?