Either the assassin sister isn't aware that it was Elena that killed her sister, or she considers the people who sent them to their deaths(albeit unintentionally) responsible. Hard to say for certain. In any case, this was a great way to wrap up the series. A pity we won't be able to see more of their antics, but things ended happily more or less. Just not for everyone(rest in pieces, yakuza).
Great piece of work. A little drier and less whimsical than most of Sayman's works, but I loved the characters till the very end.
There was promises made and fulfilled, and the ending wraps it well even though there was a time skip.
Wait, what happened to the afterward/omake? It's basically a throwaway gag, but I'm almost positive I saw it here before.
Basically, the two guys from c12 go back to the hotel after eating, Becky hands them a monstrous hotel bill... and one of them's like, "Huh. Is the date on your phone screwed up too?"