Eloisa was parabatai with Silas Pangborn. The pair fell in love with one another, an act forbidden by the Clave. In 1857, the pair was present during one of the meetings discussing the Accords in London.
Eventually, Silas committed suicide and left a note that revealed to everyone his feelings for her. Their story became known even among future Shadowhunters generations, as an example and warning set for other parabatai to not be involved.
- Vampires, Scones, and Edmund Herondale (first appearance)
- Clockwork Prince (first mention)
- Lady Midnight (mentioned only)
- Lord of Shadows (mentioned only)
- According to Cassandra Clare, Eloisa returned Silas's feelings as well and eventually died after the latter's suicide. Whether there is a connection to their deaths and them falling in love prior will further be explored in The Dark Artifices (through the parabatai pair Emma Carstairs and Julian Blackthorn).