* AngelDevilShipping: Well, shipping [[HoYay Gerald and Damien]]. Combines a bit with MindGameShip.
* FoeYayShipping: '''Guess'''. Although the "foe" part is pretty much over by the end of the first book.
* HoYay: Bucket loads of it between Gerald and Damien. In fact, it's impossible to find any fanfiction that's not slash.
** It probably has something to do with the mix of hatred, respect, and grudging admiration (that last one at least for Damien) they have for each other.
** In the first book, Damien spends more time thinking about Tarrant then he does even thinking about Ciani during their journey. Sure, it's nothing positive at first, but by the third book, him and Tarrant are nearly on FirstNameBasis and SnarkToSnarkCombat terms.
* MoralEventHorizon: Essentially, Tarrant had to cross this to gain his immortality--he did it by killing his family. Damien spends most of the series trying to drag him back.