What do you do if you hate your mom's boyfriend but she loves him?

Make him yours!

Well, he's your sister's boyfriend, so it's her choice to break up with him or not. If you don't like that choice, you should not try to break them up, or you might get in serious trouble!!

I tried to do that with my sister, and I got grounded for 2 weeks! My sister sure got angry at me, because I did all sorts of things to break them up. Really random.

If you are a twin of your sister's, and you like the boyfriend, I suggest to try to be nice to him and don't really impress him that much. It may be embarassing for your sister, and you!

If your sister's boyfriend is really mean to you, tell your parents and friends or something... express your feelings to someone.

If you don't necessarily like your sister's boyfriend, like he's taking up your schedule with your sister, then you should do something about it. Tell your sister that. Like if your sister was friends with you, and then her boyfriend destroyed you and your sister's relationship.

If your sister and boyfriend are both mean to you, then tell someone!!!

If you want a more creative way to break them up, you can hire a spy/bodyguard. Celebrities such as Chuck Norris don't work well because they draw too much attention. So do big ones. I would suggest a scrawny-looking guy who is a black-belt. Have him warn the boyfriend, and if that doesn't do the trick, then have him take the boyfriend to the woodshed.