You know I didn't think about until now but why shark teeth? Is this some fetish I'm not aware of? Monster girl adjacent?
I think it is something to do with it being monster girl adjacent, but also the fact that nobody in real life would have real pointy teeth so in anime media its a nice quirk to see.
human see pointy object human become aware
It's basically the whole "yaeba" cute little fang taken to the logical extreme.
Effectively "what's better than one cute fang?" "All of them."
To be specific,there's actually little acknowledgement about teeth,even vampire series hardly mention their teeth in any sort of proper regard,usually just a throwaway statement or a visual gag.
Monster girl has shark teeth?,done,nothing else said.
Some comedy has one character portrayed with a buzz saw for a jawline?,cool,never touched upon.
Also,nobody in real life who is born normal would have sharp teeth,but
making ones' teeth sharp has been a tribal thing since forever.
Of course,the person receiving this will be concious as files,hammers,and/or whatever other implement is needed gets directed at their otherwise healthy chompers.