I'm stuck between understanding and what

"You could make a great sadist."

I feel like I'm missing some context?

An Idolmaster doujin about donuts, and Kirari is nowhere to be seen.

I do not understand.

I clicked for the title immediately

-nods knowingly- Donuts, son.

Noriko Shiina (13): likes donuts
Tokiko Zaizen (21): hates men, is a sadist

the ultimate combination...

It's a potential to be s&m couple....

This was cute

Wish ShizuToki was as popular as TokiNori, though. :'(

nice feeling

noriko's attraction to tokiko's sadistic face (annoyed face) shows her potential (desire) to be tokiko's sub. it's subtext. (pun intended)
she'll be a bit of a bratty sub 7+ years later lol.