So, he's either gotta kill his sister or be incestuous with her. AIGHT LET'S SEE.

Fuck: Magnus. ALL DAY EVERY DAY.
Marry: Isabelle. They could keep separate rooms and NEVER EVER speak about this to anyone EVER.
Kill: Jace. Everyone tries to kill him, he's used to it. His ~ specialness ~ would save him, I'm sure.