I miss you. Every day I miss you.

–Diego to Cristina Rosales, Lady Midnight

Diego Rocío Rosales is a Centurion—in fact, one of the youngest to ever graduate from the Scholomance.


Early life

Diego and his family grew up in Mexico. Diego was a skilled Shadowhunter. He attended the Scholomance at a young age when it was reopened after the Dark War.

Diego was in love with Cristina Rosales, and they had plans to marry while Cristina also planned to become parabatai with his younger brother, Jaime. Cristina's mother greatly approved of their union.

Jaime, however, had a devilish spirit—his brother only planned to stay close to Cristina for her family's influence, to gain control over the local Institute. One night, an intoxicated Jaime reinstated this to Diego, who remained silent to let him talk it all out. Unbeknownst to them, Cristina overheard their one-sided conversation and, brokenhearted, abruptly fled to Los Angeles to get away from them, her sudden departure devastating and surprising him, clueless to why she did so.[2]

Los Angeles

After graduating from the Scholomance, Diego heard of reports of necromantic magic activity in Los Angeles, and of Emma Carstairs's belief that her parents were killed by something other than Sebastian Morgenstern's army, and went to investigate. He first visited the Los Angeles Institute to talk with the head, Arthur Blackthorn, but was immediately turned away. Deciding to investigate the matter on his own, he bought weapons at the Shadow Market, specifically from Johnny Rook, who tricked him into buying bolts tinged with belladonna poison.

The investigation led him to the body drop behind the Sepulchre Bar, shortly before Emma and Cristina arrived at the scene to investigate as well and they never crossed paths. There, she found Followers of the Guardian beating Ava Leigh and stopped them. Ava Leigh escaped and he tracked her down to the house where she lived with her boyfriend, Stanley Wells, who was also the latest victim of the killings in L.A.. While there, Emma and Julian Blackthorn arrived; not recognizing them, he assumed them to be murderers. He managed to hit Julian with his bolts, not realizing that he was a Shadowhunter and that his bolts were deadly poisonous, and fled when Emma began to get close.

While chasing down Casper Sterling, a member of the Followers, he ran into Emma and Cristina. Though shocked, he was also delighted to see Cristina again. He later fought alongside Cristina, Emma and the Blackthorns to rescue Octavian Blackthorn and prevent the warlock Malcolm Fade from sacrificing the former to resurrect his lover, Annabel Blackthorn.

When the Clave was finally alerted to the recent events, Diego stood by his decisions and testified to Robert Lightwood that he believed that the Blackthorns' did what was necessary. Robert decided not to punish Diego or strip him of his position because he was supposedly one of their best warriors. Diego and Cristina later reconciled.

Physical description

Diego has thick, dark hair, dark eyes with high cheekbones, and olive-toned skin.




Diego is a masculine Spanish name, possibly a shortened form of Santiago, which means "Saint James", derived from Spanish santo "saint" combined with Yago, an old Spanish form of James, the patron saint of Spain. In medieval records, Diego was Latinized as Didacus, and it has been suggested that it in fact derives from Greek διδαχη (didache) "teaching".[3] Diego is also considered the Hispanic version of James—primarily due to their connection with the biblical character Ya'akov (Jacob)[4]—which means "supplanter; he that replaces".[5]

His maternal surname Rosales was derived from the Latin word "rosa" and is the plural form of the Spanish word "rosal", both of which mean "rosebush".[6] His paternal surname Rocío is of both Italian and Spanish origin, where it means "dewdrops", or simply "dew".[7][8][9]


  • Diego's favorite meal is breakfast, to the point where he also enjoys having breakfast food for dinner. When he was growing up, he would often get up early to surprise his family with chilaquiles.[10]
  • Diego's favorite weapon is the axe.[10]
  • He was initially set to be younger than Jaime.[11][12]