Need help finding a series about a loner who ends up being friends with gals

[Kippithekappamancer]

Hello, I hope you can help me with my earworms. I've read this series long time ago, and I've gone through my library twice to no avail. The MC is a loner who ends up being friends with FMC, who also has communication problems, because he is a fan of her work (I can't really remember if she was a mangaka/secret idol). I remember his second friend is a gal with has shark teeth with mean eyes; they met because she's also a fan of FMC. The first time they met was at this family restaurant, where FMC saw MC seemed to be having fun with this gal, causing misunderstandings. This gal started calling him names like otaku/gross but mellowed out later on, they even had a Christmas chapter where they traded gifts.

Also the second gal became a bit popular; I remember the scanlator team going out of their way making an appreciation page of her, with her pictures in place of Maggie's from that Simpsons episode which make up the words "Do it for her".

Imagine the amount of earworm from being able to remember these details but not the title

 

[undeed]

long time ago

that the manga is old, MF is a fan of FMC, reminded me of Tonari no Kashiwagi-san
but there's no shark-teeth girl there
so it must be not that old, eh?

 

[Kippithekappamancer]

that the manga is old, MF is a fan of FMC, reminded me of Tonari no Kashiwagi-san
but there's no shark-teeth girl there
so it must be not that old, eh?

Yep it's not that old, but old enough to make it impossible to find by going through my reading history.