Shadow and Bone
David first appeared in Shadow and Bone when Genya Safin took Alina Starkov to the workshops to pick up her glass discs. He was either unaware of Genya's crush or uninterested because he never acknowledged her presence. David was a skilled Fabrikator and the Darkling used him to create the collar for Alina out of the Morozova's Stag's antlers.
Later, David admitted that he felt bad about creating the collar, and Alina told Genya to let him know she forgave him.
Siege and Storm
When Alina Starkov returned to the Little Palace, David mostly ignored her, as he felt extremely guilty for making Morozova's Collar. Alina cornered him in the workshops, and he told her about his idea for the large dishes. David and Nikolai Lantsov worked together on the dishes and the repair of the Hummingbird. Alina cornered him again and asked about Morozova's journals. During the Darkling's attack, he attempted to use the remaining dish, but it didn't work. When the Darkling revealed Genya, David rushed over to her, and they went with the other Grisha to the White Cathedral.
Ruin and Rising
When Alina was stuck in the White Cathedral, he created a salve to help heal Genya's wounds as well as searched Ilya Morozova's Journals in hopes of finding any clues to lead the dozen living Grisha and company to the Firebird.
Every morning in the White Cathedral, he also helped The Apparat in his morning prayer ceremonies by controlling Inferni flame through a smaller dish crafted from salvaged glass.
Contrary to Genya, David was present for the final battle at the Fold.
King of Scars
Rule of Wolves
Personality and traits
He was a rather quiet Durast who enjoyed using his Grisha talents of manipulating metal and didn't seem to notice anything other than that. As an adult man, his appearance was still described as unassuming and his personality was mild mannered, calm, intellectual, and distracted.
David was described as a pale, reed-thin man with long brown hair that fell into his eyes.
Powers and abilities
David's relationship with Genya started mainly after she received her scars. The two were seen as a pair in Ruin and Rising and constantly chatted about metals, melting points, and poison as the dozen made their way to the Firebird's location. Sometime in Ruin and Rising the two were seen together in bed after David kicked everyone out of the dorm to have time with Genya. The two are later interrupted by Alina telling David to "get dressed".
The two get married in the three year period after the Ravkan Civil War and before the events of King of Scars.
In Rule of Wolves, Genya and David have a more elaborate wedding ceremony at the royal chapel, and later a wedding reception. David left hurriedly in the middle of dancing with Genya to work on an idea, and was killed when Fjerda bombed the palace.