You've probable seen the video (or read the blog post) that explains consent in terms of serving tea. It's a pretty simple idea that basically says you wouldn't force someone to drink tea, so you shouldn't force someone to have sex. There are a few reasons why this isn't as great a metaphor as the internet is making it out to be. The first is that a lot of sexual assault perpetrators know the rules of consent and don't care. The second is that drinking tea is an act completely devoid of the messy emotions inherent in sex. And it's that context that makes consent difficult. I made a video explaining why.