<p>^your question was answered. several posters here said it’s inconsiderate and rude. aside from the obvious, it’s bothering your roommate. you could at least do so out of respect for her.</p>
<p>why not chew with your mouth open?
why not talk loudly on a cell phone?
why not let doors slam in people’s faces?</p>
<p>only somebody who’s on the socially clueless train would have trouble comprehending this.</p>
<p>hell, i’m a guy, i live with three women (2 sisters and my mother) and i know damn well not to ever leave the toilet seat down or i’m getting chewed out. as i would probably deserve to be too.</p>
<p>answer: it’s inconsiderate to your roommate. if it’s bothering her and it’s not like she’s asking you to make a huge adjustment or anything unreasonable, just put the toilet seat down.</p>