- This article is about the Knight. For the female Warden of the same name, see Yoshimo.
In Death Masks, Shiro is disguised as an old derelict when Harry first meets him in an alley while Harry is being chased by a big four-eyed, bear-like creature. Harry tries to tell him to run. Instead, Shiro asks him to hold his glasses, then faces the creature with his light-emitting sword raised, power humming from it. Shiro ask Ursiel, the Creature to "Let him go", refusing, they proceed to fight, Shiro does so most elegantly. Harry knew then that he was a Knight of the Sword. After Ursiel is killed, Shiro stops Harry from picking up the coin that had fallen out of the corpse.
Shiro tells Harry that man sees faces, skin, flags, membership lists, files, God see hearts. 
In Death Masks, Shiro agrees to be Harry's second in the duel with Duke Paolo Ortega of the Red Court. He set the meeting with the mediator and the seconds for that evening at Mac's. Shiro suggest to Harry tha tit is better to not fight, that it's always smarter not to fight. If both parties want to quit, then the duel over. And, that maybe Harry is not as locked in as he believes he is. So, Harry tries to suggest to Ortega that they both walk, but naturally, that doesn't work out. Shiro negotiated a Duel of Wills at Wrigley Field in the meeting with mediator.
Shiro has fought many duels in the past, either to protect someone, or force something to leave an area, or to fight without involving others. He had fought two duels with Vampires, one from the Jade Court, the other from the Black Court. He also fought two duels with Denarians, saying that they do not honor their agreements and indulged in treachery both times.
Father Forthill tells Harry that Shiro is one of only two Knights of the Cross that have ever faced Nicodemus Archleone, and survived. It's the reason why Nicodemous was willing to trade Harry for Shiro.
Later, Shiro is found in the chapel at O'Hare Airport, brutally tortured and nearly dead. With his dying breaths, he gave his sword Fidelacchius, the Sword of Faith, to Harry Dresden in trust until Harry could find the one it belongs to. He tells Harry to trust his heart when Harry asked how would he know who to give it to. He tells Sanya goodbye and that he's proud of him. Sanya kisses his head. He tell Michael that the fight is now his and to be wise. Tears fall down Michael's face. Shiro tells Harry that Nicodemus is afraid of him, afraid that he saw something and to not let the Denarian unmake him. Also, that Harry taking the shroud from him will undo the plague curse immediately.
At the end of Death Masks, a letter of his, postmarked two weeks previous, is delivered to Harry Dresden, in which he reveals the foreknownledge about his death as well as his illness. Knowing he would soon die anyway, he gave himself up for Dresden.
Shiro was diagnosed with terminal cancer. His family knew, but he did not tell Michael and Sanya.
In Small Favor, Sanya tell how Shiro found him after he threw his ring into a Venice canal. How Shiro took him to Malta to meet with the angel Michael, where he was given the sword Esperacchius and the chance to be a Knight of the Cross.
He has white hair, heavy eyebrows, and wears a short white beard around his chin. He wears thick corrective glasses.
Shiro Yoshimo is Okinawan. He is a descendant of Sho Tai, the last king of Okinawa.
Michael says he had a gift. He could "swordplay like Mozart knew music".
- ↑ 1.0 1.1 1.2 Death Masks, ch. 06
- ↑ 2.0 2.1 Death Masks, ch. 07
- ↑ 3.0 3.1 Death Masks, ch. 15
- ↑ Death Masks, ch. 22
- ↑ Death Masks, ch. 27
- ↑ Death Masks, ch. 31
- ↑ 7.0 7.1 Death Masks, ch. 33
- ↑ 8.0 8.1 Small Favor, ch. 15
- ↑ Small Favor, ch. 20