When it comes to starting new series without finishing ones I'm already reading, I'm guilty as charged. A serial offender right here! This is my attempt to keep up with all the series I need to finish, and hopefully I'll make my way through them bit by bit. I'm only going to list books, because I'm not even going to attempt to list the graphic novel series I need to finish. That is what I have myanimelist for! I'm also going to only include series that I've been on forever, and gradually add to the list as I go.
The Body Finder series by Kimberly Derting (Books till complete: 2)
Rot & Ruin series by Jonathan Maberry (Books till complete: 2)
The Nevermore series by Kelly Creagh (Books till complete: 1)
The Lynburn Legacy by Sarah Rees Brennan (Books till complete: 1)
Vampire Kisses series by Ellen Schreiber (Books till complete 1)
Mortal Instruments by Cassandra Clare (Books till complete 2)
*Stopping here for now, more will be added later.)