You were flirting with this girl, and Ayano came up. She started arguing with the girl, and eventually just kinda started yelling about how she would be the only one who would never leave you.

Ayano: "Senpai if a thousand girls like you I'm one of them! If a hundred girls like you I'm one of them! If ten girls like you I'm one of them! If one girl likes you it's me! And if no girls like you I'm fucking dead!'