I'm starting to think the murderer didn't plan to kill all these girls at first, but rather every girl he dates, he finds a flaw in and thinks he has to kill them. The "not again" lines make it seem like he either regrets having to kill them, or is at least disappointed that they all turn out unworthy in his eyes. This doesn't match his attitude in "It's Pretty Hard To Beat The King" though, because there he seems like he's doing it all on purpose to gain fame (or infamy).
I'm starting to think the murderer didn't plan to kill all these girls at first, but rather every girl he dates, he finds a flaw in and thinks he has to kill them. The "not again" lines make it seem like he either regrets having to kill them, or is at least disappointed that they all turn out unworthy in his eyes. This doesn't match his attitude in "It's Pretty Hard To Beat The King" though, because there he seems like he's doing it all on purpose to gain fame (or infamy).