Black Butler season 5 episode 4: Finnian's backstory is revealed as Sebastian starts serving Sieglinde as her butler

Black Butler season 5 episode 4, titled His Butler, Serving, was released on April 26, 2025. In the episode, Sebastian Michaelis began his duties as Sieglinde Sullivan's butler. He served her bed tea and taught her English and proper table manners. The episode perfectly encapsulated Sebastian's character, as he maintained composure while performing his duties.

Black Butler season 5 episode 4 also revealed Finnian's backstory, including his previous identity. It was disclosed how Ciel and Sebastian changed his life. As a result, the episode captured Ciel and Finnian's dynamics. Moreover, the latest episode added depth to the narrative with an interesting finish. Undoubtedly, Cloverworks has done a decent job portraying the narrative from Yana Toboso's original manga.

Disclaimer: This article contains spoilers from Black Butler season 5 episode 4.

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Black Butler season 5 episode 4: Sebastian serves Sieglinde as her butler

Sieglinde, as seen in the episode (Image via Cloverworks)

Picking up the events from the previous episode, Black Butler season 5 episode 4 begins with Sebastian Michaelis entering Sieglinde's room and serving her a Ronnefeldt's Ceylon Blend tea she's unfamiliar with. Sieglinde Sullivan is momentarily surprised by the unfamiliar presence and mentions that she has never had wake-up tea.

Sebastian notes that a butler must ensure their master has a refreshing beginning to the day. The demon butler's grace impresses Sieglinde as she asks Wolfram to take notes. Following that, Black Butler season 5 episode 4 shows Hilde helping Sieglinde get dressed. The girl says she doesn't want to wear it. Rather, she wants to wear something foreign.

Sebastian and Sieglinde in the episode (Image via Cloverworks)

Hilde doesn't know what to do because only a handful of dresses are available. As such, Sebastian takes a bed cover and transforms it into a beautiful dress, much to Sieglinde's surprise and delight. During breakfast, Sebastian instructs Sieglinde on table etiquette and points out her poor manners. He tells Sieglinde that she's using her silverware in the wrong order.

Sieglinde, who has never been taught such manners, feels it's fine as long as she can eat. However, Sebastian corrects her methods. He mentions that a landlord must value dignity above all else. Thus, he teaches Sieglinde proper table manners. Wolfram is slightly offended by Sebastian's harsh words and methods, but the demon butler reminds him that it's a butler's duty not to spoil and pamper their master all the time.

Wolfram, as seen in the episode (Image via Cloverworks)

Interestingly, Sieglinde doesn't mind and asks him to teach her more such stuff. Meanwhile, in the kitchen, the Phantomhive servants, especially Baldroy and Snake, disapprove of Sebastian's cold behavior as he serves under a new master. However, Tanaka is convinced that Sebastian must have a plan. He informs other servants that a butler mustn't only worry about their master but ensure their master returns to a perfect situation.

Following that, the narrative for Black Butler season 5 episode 4 shifts to Sieglinde's room, where she asks Sebastian to teach her English. The butler then presents her with a summary of English folk remedies - a book he knows might be challenging for a beginner.

Yet, Sieglinde becomes engrossed with the subject and asks Sebastian about various potions. While Sieglinde is busy reading the book, Wolfram steps outside momentarily and encounters Hilde, Anne, and Grete. Hilde warns Wolfram that outsiders are a bad influence on the girl.

Finnian and Ciel (Image via Cloverworks)

However, Wolfram states that he cannot do anything to stop Sieglinde's affection for them. Elsewhere, in Black Butler season 5 episode 4, Finnian attempts to feed Ciel. Yet, the boy doesn't want to eat and hides his face in a blanket. As such, Finnian follows Sebastian's advice and gives Ciel some milk with honey. While feeding him the milk, Finnian accidentally blows it into Ciel's face.

He then gently wipes his face and asks Ciel if he will go outside for some fresh air. However, the boy doesn't want to go, as he feels it's scary outside. Finnian then assures Ciel that he will protect him no matter what happens - something he decided to do from the moment Ciel gave him the name "Finnian." However, Ciel tears up and says that he's not worth protecting. In response, Finnian begins to weep as well.

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Black Butler season 5 episode 4: Finnian's shocking past is shown

Finnian's past, when he was known as Specimen 12 (Image via Cloverworks)

The narrative for Black Butler season 5 episode 4 then delves into a flashback to reveal Finnian's past. The flashback scene shows a few agitated doctors eradicating all files and specimens related to their research due to a raid. Finnian, who used to be known as specimen number #12, hears the clamor on the upper floor. Suddenly, a doctor appears and shoots two boys beside him.

The doctor attempts to shoot Finnian next, but the boy's eyes glow, and he violently eliminates all the doctors in the lab. After that, he tries to flee from the underground laboratory. As he ascends to the ground level, he encounters Ciel and Sebastian. Ciel Phantomhive then stares at the boy and asks for his name.

Black Butler season 5 episode 4 then returns to the present and shifts the perspective to Finnian, who tells Ciel that he wouldn't be here without him. He mentions how he learned to grow things instead of destroying them with Ciel's help. Moreover, the boy mentions that it's Ciel who turned him from specimen number #12 to Finnian.

Sebastian tells Sieglinde about Ciel's past (Image via Cloverworks)

Soon after that, Sebastian and Sieglinde enter Ciel's bedroom. The latter changes Ciel's bandage and observes that his eyes are healing rather quickly. Shortly after, she leaves the room with Sebastian. Black Butler season 5 episode 4 then shows Sieglinde asking Sebastian whether they are devil worshippers. She believes they are because of the seals on Ciel's left eye and Sebastian's hand.

At this moment in Black Butler season 5 episode 4, Sebastian Michaelis tells Sieglinde that Ciel was once kidnapped by a certain Demon-Worshipping organization to be a Demon's sacrifice. Sebastian had met Ciel during the summoning ritual. The demon butler tries to say more, but Sieglinde tells him not to, realizing it must be a sad story for him. She also promises to keep it a secret from others.

Later, Sieglinde informs the Phantomhive servants that Ciel Phantomhive's recovery is going well. Baldroy feels they should return to the Phantomhive manor as soon as Ciel can move. Interestingly, Sieglinde shows hints of reluctance at Baldroy's words. Yet, she nods her head in agreement. On the other hand, Wolfram asks Sebastian to prepare dinner.

Snake and Sebastian discover a secret passageway (Image via Cloverworks)

During the preparations, Sebastian finds out that they are out of white wine for cooking. Wolfram then informs the demon butler that the wine cellar is down the stairs in the right direction. Black Butler season 5 episode 4 then shows Sebastian descending the stairs with Snake accompanying him.

However, instead of going right, he chooses the left route and reaches a dead end. At this moment, Sebastian investigates the wall and locates a secret passageway. Black Butler season 5 episode 4 ends on a chilling note, with the demon butler and Snake witnessing an eerie staircase leading to an unknown place.

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Conclusion

The Phantomhive servants in the episode (Image via Cloverworks)

One of the highlights of Black Butler season 5 episode 4 was how Sebastian Michaelis quickly adjusted to being Sieglinde's butler. It shows his devotion to Ciel because the demon butler knew that Sieglinde was necessary for Ciel's cure. Hence, he had to obey the witch's demands. Yet, she wasn't a menacing figure.

Rather, Sieglinde was unaware of how the outside world worked. Therefore, Sebastian acted as her guardian, teaching her everything she needed to know. On the other hand, the episode revealed the shocking backstory of Finnian, who was a test subject prior to meeting Ciel and Sebastian. At the same time, the cliffhanger ending at the end only added mystery to the Emerald Witch Arc.

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