Slime Castle, and New Functions

Slime Castle, and New Functions (スライムキャッスル、そして新機能.) is the fifth episode of the In Another World With My Smartphone anime.

Plot
The episode begins with Touya and the girls (Elze, Linze, Yumina, and Yae) traveling to their next destination by cart. The girls are less than thrilled about their next guild quest, which involves searching the castle of a slime researcher who has gone missing. Touya tries to cheer the girls up before they arrive at the castle though they become skeptical of his enthusiastic demeanor towards this quest. Still, he immediately denies it while accidentally and comically hurting Kohaku.

Touya and the others arrive at the castle. As they enter, Touya is hit in the head with a wash basin that fell from above; while Touya is reeling from pain, Yumina notices something is happening with the basin. The group are surprised when the basin turns into a slime that none had seen before. Linze suggests that they search the castle for the owner's research documents.

They then begin to look around the castle's first floor for any clues as to what the slime researcher was working on. Unfortunately, the slimes inhabiting the castle have destroyed most of the documents they find. Linze finds a book containing illustrations and descriptions of different slimes that the researcher managed to create. Unable to find anything else of importance, Touya decides to search the rest of the castle for the location of the slime researcher.

The group then returned to the castle lobby, where they encountered a group of green slimes (a monster the girls had no interest in fighting since it could dissolve their clothes). Kohaku returns to his original size to defeat the slimes, but it proves ineffective. They are forced to retreat to the second floor when the slimes begin to approach them but are relieved when they are not followed to the next floor, which Linze believes is due to them setting up their territory on the lower floor. As they are about to proceed, Elze slips and falls on some liquid on the floor and wonders what it is until one of the others points out a group of white slimes at the top of the staircase.

Linze identifies it as a lotion slime (one of the researcher's failed creations), a type of slime that secretes a type of lubrication whenever it senses dangers. As Elze tries to get up, she falls down again, only this time she inadvertently knocks down Yumina and Touya (who also knocks down Yae and Linze) in the process. As they fall to the lower floor (with Elze dragging Yumina by her feet and Yumina bringing Linze with her), Touya is saved by Kohaku, who grabs onto his collar at the last second. Unfortunately for the girls, they land in a group of green slimes that start to dissolve their clothes; Touya can save them from the slimes by using his Gate Spell before their clothes are completely dissolved. Thankfully for the girls, the slimes that were transported also retreated to the lower floor, but the girls were annoyed that their clothes were ruined due to the slimes, with Elze attacking Touya out of sheer embarrassment.

As the group travels through the castle's second floor (with the girls wearing temporary clothes they found), Yumina and the other girls decide to destroy the castle when they are done due to their annoyance at what has happened thus far. Touya surmises that the reason for the various failures was that he was trying to create a specific type of slime but could not verify the special trait of the slime until he made it, which Linze confirmed. Touya then notices something strange about the statues before him while listening to the girls' conversation. While examining it, Touya discovers that the statue's breasts are strangely softer than they were supposed to be. Around that same time, slimes that were attached to the statues appeared, startling the party, with Linze identifying them as Bust Slimes (slimes that attached themselves to girls with small breasts to accentuate them), another one of the researcher's failed experiments. Simultaneously, the slimes try to attack Yumina (for obvious reasons), though Yumina destroys them with one of her wind attribute spells before they could succeed. Yumina mutters that she's still developing.

They later find the office of the slime researcher in which they find his remains having died some time ago. Touya finds his journal in which he states that he had successfully achieved every man's dream while trying to figure out what he meant by that Yumina alerts him to something nearby. When he looks at the place Yumina had pointed out, Touya spots four slimes starting to change their shapes. When the slimes finished transforming, they turned into near-identical copies of the girls, which surprised him, while the others looked at them, stunned. When the girls notice how Touya reacts, they try to get him to look in various comedic ways, culminating in Elze hitting him on the head with her gauntlet again.

Sometime later, the castle is burning with the girls watching blankly, glad the deviant research is destroyed. Touya is perplexed the researcher wanted to create slimes that could turn into naked servant girls. Kohaku asks Touya to take him to a human town, to which he agrees. Later that day, Touya walks through the town to show Kohaku around ( while carrying him in his arms). While observing the town, Kohaku notices Yae nearby trying to talk to a crying little girl. When Touya speaks to Yae, she tells him that she found the child and was trying to help her, but she wouldn't respond to her questions no matter what she tries. Kohaku tries to talk to the girl and learns that her name is Lim, though when Touya tries to use his Search Spell to locate any of her family, he cannot locate anyone within his range. He then decides to use the map function on his smartphone to amplify the effect of his spell and successfully finds her mother.

After reuniting the separated family, Yae asks Touya how he found her; he explains that he used a feature on his smartphone to enhance the effect of his Search Spell. She requests that he tries to locate her brother, to which he agrees; he can then locate him in an area Yae confirms to be their family's dojo in her homeland.

In the inn later, Touya casts Enchant: Long Sense on his phone before using the camera function. He sees the bed in the room across the hall and pans to the back of it to find Linze in her underwear, putting on her tights. He can't help but peek; he turns off the camera once she's done. Moments later, Linze knocks on his door and enters. Embarrassed, Touya deflects her concern. Linze asks him to help her learn ancient magic from a scroll. Touya creates and enchants glasses to allow her to read the spells.

Linze practices the spell Ballistic bubble bomb, but can't get it to work and runs out of mana. While she rests a bit, Touya thinks of something. When Linze attempts again and wears herself out, Touya uses Null magic to replenish her mana with his own surplus. Touya advises Linze to picture an exploding bubble to help master the spell.

Sometime later, Elze breaks her gauntlet. Touya takes her to buy replacements. While walking back, Elze is entranced by a gothic lolita dress in a shop window. Touya convinces her to try it on, finding her beautiful. Touya buys it as a gift, so Elze can't refuse to own it, and Elze wears it out. Yae, Linze, and Yumina find the dress suiting for her.

Yumina gets a letter from her father, who wishes Knight Touya as thanks for his help.

Characters

 * Touya Mochizuki
 * Linze Silhoueska
 * Elze Silhoueska
 * Yae Kokonoe
 * Yumina Ernea Belfast
 * Kohaku
 * Lim (debut)
 * Charlotte (flashback)
 * Aer (cameo)
 * Micah

Spells Used

 * Gate Spell
 * Cyclone Edge
 * Search Spell
 * Transfer Spell
 * Bubble Bomb

Notable Places

 * Slime Castle
 * Silver Moon Inn
 * Alephis Capital City

Types of Monsters

 * Green Slime
 * Lotion Slime
 * Bust Slime

Media Counterpart
Footnote: &dagger; - Partially Nonexistent - 50% or more storyline is missing. &Dagger; - Not Chronological - For Chronological Order, See Media Counterpart

Differences

 * In the Light Novel, Touya, and the others didn't visit the Slime Castle until after going to Mismede. In the anime, it happens right at the beginning of the anime adaption of the 2nd light novel.
 * In the manga, Linze and Elze are having their period shortly after the events of Kohaku's summoning and are staying in bed. Touya doesn't get what Yumina means by them being "unwell" at first, forcing both Yumina and Yae to flusteredly delicately explain it's not a cold leaving them in bed.

Trivia

 * This is the 2nd episode that uses the Elze version of Junjō Emotional.
 * In the manga, Linze changes her shirt after returning to her room.
 * Kohaku is soon to be constantly squeezed to near death by Touya and the others during various scenes in the episodes, mostly due to them trying to deny something the others had mentioned. (Yae trying to deny her feelings for her brother)
 * The God of Love may have been behind the girls falling into the green slimes. Touya had been fantasizing about it for a long time, so that she may have granted his wish.