。
I was drawn to that girl.
Literal
I [topic-は] that girl [to-に] was-drawn.
ひかれる is the passive of ひく (引く, 'to pull'), meaning 'to be pulled/drawn [toward].' The target of attraction is marked with に. Often written in hiragana (not 引かれる) when used in the emotional/romantic sense to distinguish from literal pulling.