I'm not sure what "it" means in this sentence.
Answer from a Native speaker
I'm guessing that "it" here refers to the action mentioned just previously, which is walking into the metaphorical "fire of love." When "it" is used in a sentence and the meaning isn't immediately clear, it's most likely referring to the action or idea mentioned just previously. Ex: A: Where's the car? B: It's in the garage. Ex: A: Look at that cat! B: Wow, it's so cute.
1/2 STEP LEARN