BPD/NPD relationships exist
The Narcissistic / Borderline Couple: New Approaches to Marital Therapy https://www.amazon.com/dp/0415934710/ref=cm_sw_r_cp_awd_TdpbxbG7SNB13
Joan Lachker is your best bet for understanding the dynamic duo of Narcissistic/Borderline couples.
This book from her is a great primer and read.