Siglai

"I like you, Sigma! Out of all of us, you're the one who acts the most ordinary when you're surprised!"

- Nikolai to Sigma in Chapter 78.

Siglai is the slash ship between Sigma and Nikolai Gogol from the Bungou Stray Dogs fandom.

Canon
Sigma and Nikolai are both members of the Decay of Angels. Not much is known about their first meeting or their interactions prior to on-screen events, however, Nikolai has a genuine liking for Sigma to an extent where he mourns Sigma’s supposed death. He trusts Sigma enough to unveil his left eye and explain his ideals and goals with freedom. Nikolai is childish and dramatic around Sigma, teasing him and enjoying his reactions greatly, stating he likes how normal and ordinary Sigma is.

On the other hand, Sigma is wary around Nikolai, finding him odd and irritating; he states he hates dealing with Nikolai the most and appears unamused and annoyed by Nikolai's theatrics. Sigma has a level of respect for Nikolai despite harboring some dislike towards him and finding him a nuisance; Sigma claims he has no doubt regarding Nikolai's capabilities and instead questions his state of sanity and odd plannings. Nikolai views Sigma as a valuable asset to his plans. Sigma is rather accustomed to Nikolai’s chaotic behavior and states he hates dealing with him the most, leading to the implication that they’ve worked together on multiple occasions.

Kamui Revelation Arc
It’s not stated when Sigma and Nikolai first met, however, their first interaction shown in the series was when Nikolai saved Sigma as he was falling to his death from the casino. As Sigma fell from the sky awaiting death, Nikolai stands on the cliff and looks up laughing. Sigma wakes up with Nikolai standing by him, who was waiting for him to wake up. Nikolai remarks with a smirk, “Are you awake now?” to which Sigma splutters in shock and exclaiming, "Gogol?! Why are you here?!" Nikolai grins and shouts, "Ahhh! This is great! That look of surprise! You're such a normal guy!", leaving Sigma sweating upon his rambling. Sigma then notices how he doesn't have a scratch after his fall from the casino, and Nikolai states the trick is easy with a grin on his face as he explains how he used his ability to gradually decrease Sigma's fall and heal the wound on his chest. Nikolai shouts, "It's a bloody miracle!" leaving Sigma in silence, unamused and in thought. Sigma remains seated on the ground, examining his wounds as Nikolai swings his baton around boredly. Sigma mumbles to himself wondering why he was rescued by Nikolai considering Fyodor had likely ordered his death. Sigma then retracts his statement, instead going on to ponder how Nikolai is still alive, given the events of Nikolai's "death" in the hostage situation. Nikolai offers his hand to Sigma, telling him, "Why don't you ask me? I'm right here.", leaving Sigma with a grim expression and asking how Nikolai survived. Nikolai then puts on a "cute face" and says, "Oh, gee, how did I? Asking a magician to reveal his tricks is a bit rude, no?" teasing Sigma who glares and thinks to himself, "I hate dealing with this Decay member the most..." Nikolai then responds saying he's kidding, going on to say, "I like you, Sigma! Out of all of us, you're the one who acts the most ordinary when you're surprised! So, I'll tell you!"

Nikolai reveals his death was a mere illusion via his ability, leading Sigma incredulous, confusing Nikolai. Sigma then states that he knows Nikolai is capable of faking death since he's a "crazy, anything-goes" skill-user. Sigma asks why Nikolai faked his death contrast to the original plan that required his genuine death. Nikolai then takes off the card masking his left eye, smiling grimly while going on to explain how he intended to die but then remembered how he was understood by Fyodor, leading to his realization of wanting to kill Fyodor to be freed from human emotions. Nikolai laughs and announces he's going to kill Fyodor, and Sigma watches in horror, realizing how insane Nikolai is as Nikolai leans in and puts his hat over Sigma's head, stating he wants Sigma to help him find out Fyodor's skill.

Vampire Infection Outbreak Arc
Sigma and Nikolai devise a plan to break Fyodor and Dazai out of Meursault, though this occurs off-screen. The security goes into shambles as Sigma and Nikolai invade Meursault for the escape plan, and Nikolai uses his ability to free Fyodor and Dazai out of their cells. Nikolai gives a dramatic flair, announcing his arrival with Sigma as the latter stays back, watching with fatigue and annoyance. Nikolai happily explains how the plan worked, unamused by Nikolai's theatrics. Nikolai then leans over to Sigma, clapping his hands and cheering, “Applause for my assistant!” referring to Sigma who glares at Nikolai. Sigma responds, “Who are you calling your assistant?” and suggests to simply explain what’s going on to Fyodor and Dazai.

Sigma watches Nikolai playfully reunite with Fyodor, staring in bleak annoyance through the scene. Once Fyodor and Dazai begin injecting themselves with the poison, Sigma watches how the two along with Nikolai gleefully laugh, leading Sigma to fearfully ponder on how he's the only sane person in the room in fear. Sigma watches from afar as Nikolai begins to explain the prison break game, horrified. Later, Nikolai spins around dramatically and points at Sigma, referring to him as “assistant” once more and asking him to bring the “thing.” Sigma shouts, “I’m not your assistant!” in irritation. Once Sigma is chosen as Dazai’s tool, Nikolai is startled and begins to laugh, saying he likes Dazai. Afterwards, the two are separated, leaving the scene as their last canon interaction as of now.

In Chapter 111, after Fyodor successfully wins the prison break game, Nikolai asks Fyodor what had happened to Sigma, growing grim (contrast to his previous gleeful attitude) after Fyodor informs Nikolai that Sigma would likely never open his eyes again, showing that Nikolai cares about Sigma to an extent. Nikolai ponders the fate of all who oppose Fyodor, thinking over Sigma and Dazai’s demise.

Fanon
Siglai is a relatively popular ship, rivaling Fyolai and Sigzai, though often getting overshadowed by said pairings. Fans enjoy Siglai’s dynamic as Sigma is often irritated and tired by Nikolai’s antics while the latter enjoys teasing him. Shippers guess that since the two worked alongside another, they share many more interactions off-screen. Fans often joke or headcanon Sigma as a Fyolai third wheel or Nikolai’s annoyed mom. Siglai is often viewed platonically, either with Sigma and Nikolai as best friends or siblings. The ship has around 2,000 works on AO3.

Fandom

 * FAN FICTION

Trivia

 * They have a height difference of 7 cm, with Sigma at 177 cm tall and Nikolai at 184 cm tall.