Tell me about this murder trilogy?

It is the murder of Jenny. In বোরবন on the Shelf (Sawdust) she leaves him. In Midnight প্রদর্শনী (Hot Fuss) he kills her. In Jenny was a Friend of Mine (Hot Fuss) he is questioned and denies killing her. বোরবন on the Shelf is a prequel bc it was released after the murder already happened. Also in My Chemical Romances new album they refer to Jenny and tell her to come back প্রথমপাতা as an homage to the killers =)