Conor Trewhella is two years older than his sister Sapphire, and is the son of Mathew and Jennie Trewhella. He possesses Mer blood but it is not as strong as his sister's, and also belongs greatly to Earth.


Conor is very level-headed and calm, and almost always tells the truth as he hates telling lies and only does when he absolutely needs to. Ingo did not hold as much allure for him as it did for Sapphire; its main interest for him was Elvira, but they soon cut off their relationship following Elvira's contact with her Atka.

Everyone describes Conor as the responsible one. He does his best to take care of his family and others and is very kind and loyal to the people he loves. Despite these traits, he cannot forgive, forget, and/or accept nearly as much as Sapphire; for a span of time he hated his father for leaving for Mellina and Mordowrgi, though he forgave him afterwards. He does have a vengeful streak, as shown when he killed Ervys after one of Ervys's followers stabbed Mathew from the back during a duel between Mathew and Ervys, and even afterwards saying he wanted to kill Ervys again even though he was already dead.


Pre-Ingo time, Conor grew up in the cottage his family owned. At one point he took karate lessons and slammed into the door frame while practicing; the door was never able to close properly after that.


talisman - Elvira made a small mermaid figure for Conor, who believed it had his face on it. Granny Carne said the talisman would work for him only, and everytime someone else touched it, its luck would fade a bit. The talisman was not mentioned again after the third book, The Deep. The talisman was also mentioned to give great power to whomever held it, in this case Conor.