That is a lyric from one of my favorite songs and I never understood what that part meant. Thanks!!!

Ok, so now someone help me understand the 13th finger line.

Jawbreaker - Jinx Remover
Blew twelve and kissed the thirteenth finger.
"Rabbit, rabbit," on the first.
I hold my breath.
Did tricks I hoped you wouldn't notice.
A superstitious hyperrealist.
I'll make you mine.