The whole world was a mystery to Ominis. And even though he had learnt to live with his peculiarities, that didn't mean it made him feel any better. Unable to see, he relied on his senses and, sometimes, smells.

And, in fact, Ominis didn't really like smells, as funny as that sounds. They were usually acrid, pungent, and confusing. It annoyed him most of all when some pure-blooded witches spritzed their pungent and nasty perfume, and they were usually the only ones who used it

And then he could smell you, and he thinks he liked it.

Why is it that in Potions class, the whole room smells like you? They're preparing Amortentia of course, and this time he's paired with you but... Oh

It seems the realisation came to him too late.