Heulwen Dafydd is the twin sister of Mostyn and the daughter of Tesni Dafydd (youngest sister of Servalle). The twins are twenty-six years old. After a scandal of some type in Rebma, Heulwen was sent to Amber to be punished. Unlike her brother, who has tried to carve a life out of the diplomatic services, Heulwen took the opportunity to 'go wild' when released upon Amber. While she is in possession of better than average clerking skills, Heulwen has no desire to be a clerk.
Heulwen had a short and tempestuous affair with Martin following her arrival in Amber and is known to still be on friendly terms with him. She made no secret of leaving him because she did not want to be 'exclusive'. She is currently spending more time at House Karm than the embassy and may be considered less than subtle about her affairs in and with that house.
Heulwen is known to fight dirty. She often takes a beating when she does fight. The result of the injuries is a rapid healing process that her brother refers to as the 'good genes' in the family. She is known to associate with Prince Gerard and to take his advice.
Heulwen seems wont to rebellion and wild impulsive actions. Also, she is drawn to projects that require her organizational skills and tedious dedication to difficult tasks. Theses natures conflict in her and she will confess that she feels guilty about not being able to be a proper Dafydd. She wants to please her family (she strongly resents her mother) and she wants to be loyal. However, regrets make her no more suited to a life behind a desk.
The result of her impulsiveness and spontaneity may result in serious repercussions. She is well aware that the Ambassador is ignoring her actions rather than calling her on the carpet for them.
She appreciates this because it allows her the freedom to continue to work at the embassy on special projects between her adventures. She loves her family and is loyal. Still, she is enjoying the liberation of Amber. More than many, she has adapted quickly to being above the water.
She eventually became a Karm problem as a political contract for betrothal was worked out between Gilgamesh Karm and House Dafydd. The marriage never took place, but she did bear a child. Alas, Heulwen died in childbirth.