Honestly, as obnoxious as the male and female lead are in this story, they don't actively piss me off like in the worlds before this. They're good-hearted morons, and that's destructive, but not downright malicious or dickish for the most part. You can genuinely tell that their personalities are the result of shitty writing.
And to that end, I'll say that I genuinely believes that the female lead believes she didn't notice at all. There's a shit-ton of denial going on, but she isn't exactly lying.
@Maala It doesn't even need to be freshly killed men. Blood in general smells pretty damn strong and an especially bad nosebleed could leave a smell that takes a lot to get rid of.
If you wanna know exactly how it smells, well, it basically smells like iron. Probably because that's exactly what it is; blood cells rely on iron molecules to carry oxygen molecules around.