Complex sentence: Hiroki reaches out to her and she eventually begins to open up and become friends with the other girls, she is the'tsundere' character of the anime and over the time she develops minor feelings for Hiroki.
Split into simpler sentences: Hiroki reaches out to her and she eventually begins to open up and become friends with the other girls. She is the'tsundere' character of the anime and over the time she develops minor feelings for Hiroki.