Elie Smith Most likely, though, it will probably be mostly clary and jace if it does since Clary appeared to care about her very much. Also, Jem and Tessa will probably be involved because of Jem's connection to Emma, plus he told Tessa he would watch over her, if I remember correctly.
Maura I think Clary and Jace have to appear (or be mentioned) at least at some point or I will cry. And who else thinks it would be incredibly awesome if (considering how young shadowhunters do everything) they are married and Clary is pregnant?
Emily Boribon Im sure Cassandra will make sure those characters are included as she knows how much we love them. She wouldn't just forget about them, but as we know this is Emma's story, so it will be about her !
Trisha (The Tea Reader) They night when it comes to the council, and the other shadowhunters. Even though this is not their story they should make an appearance or at least be mentioned.
Mattie Yes, i have already it and it is amazing, and at the end it has a part called the long conversation were it tells more about clary,jace,magnus,alec, and others ps. Theres a few suprises
Miss Galathynius Yes! Why would all the other books have Magnus and this one not, Magnus brings Alec and he brings Jace, and he brings Clary, and she brings Simon who brings Izzy. Like a big family, so yes they are in it. They only talk about a some of them, but Magnus appears twice, and Jace and Clary are in one of the scenes. But the short story 'A long conversation' has all of them.
Dr.ShadowHallows They play small cameo's but their not particularly involved. Though you do actually get to see some of the characters during the end of the book.
Savannah lets just say that old feelings from the infernal devices will be brought back up again and im so not ready to deal with triple the feels
Liv I think they might have some appearances, but not as much as you think since this is Emma's story.
Annie yes! Jace, Clary and Magnus appear in this book. Though their physical appearance is minimal they are referred at different times through out the book.
MystaryPi It does talk about Jace and Clary, and Magnus Bane is in one of the parts, but their involvement is minimal.