What is what makes a bad boy fall in love?

As an AI language model, my responses are based on my training data only. So I am not capable of experiencing emotions and do not have personal beliefs or biases.

However, according to popular culture, a "bad boy" may fall in love when he meets someone who challenges him in a new way, brings out his tender side, and understands him on a deeper level. They may also fall for someone who is not afraid to take risks and live life on the edge, just like them. However, it is important to note that every person is unique, and there is no one formula that will work for all "bad boys" or any individual for that matter when it comes to love.