Which is 9?
I get it! It's because 8 in facts is a spy and tries to make love with 9, but then is only a spy sent by 7 in order to let him 8 9.
It'll still be, that 8 might want to kill 7 2 because 8 wants to be the 1, as for desires of power among all other numbers, and also because 7's intentions are limited to cannibalism, while 8 has higher prospects for the future.
But for 8 to reach 1, he has to fight his 7 girlfriends. After fighting with 6, 7 falls in love with her, and he changes his plans and fight all 1's girlfriends (6's lesbian girlfriends) in order to prove his love to 6.