I'm sorry, I haven't heard of the 'Kitkat Zobel love story' specifically. It might be a very unique or personal story within a certain community or group.
Toge Inumaki is important too. His special cursed speech ability makes him stand out. Also, the principal of the school, Masamichi Yaga, is likely to be important as he is in a position of authority and has an influence on Gojo and the other students. There could be other characters like the members of different clans that also play roles in the complex web of the story.
It might be a story full of surprises. For example, they meet in an unexpected place, like a small coffee shop where Kitkat accidentally spills coffee on Zobel. At first, they dislike each other but as time goes by, they discover common interests and fall in love. It could also involve family drama, where their families oppose their relationship at first but they fight for their love.