Prison Lock and Grimoire Security

 is the second of the Trinity Seven  series, initially broadcasted on October 14, 2014 in TV Tokyo.

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In order to become a mage, you need a research theme which archives one of the seven deadly sins. While thinking about what his theme will be, Arata and 3 others are locked in a barrier, with no exit to be found. But then Lilith and the others find themselves needing to use the restroom... Good luck, girls!

Summary
During Lilith's class, Arin stares at an uneasy Arata while the remaining students watch. Arata questions Lilith about the situation although she is unsure as well.

In the cafeteria, Arin simply continues to observe Arata while he tries to eat.

While strolling through the halls, Arin follows Arata until she tries to enter the men's restroom with him, much to his bewilderment. Afterwards, he questions her reason for tailing him which Arin eventually responds that she was observing the Demon Lord Candidate as his partner before leaving.

Later, Arata is surprised to discover Lilith, Selina and Levi occupying his room. Both Selina and Levi explain their desire to gather information while Lilith states that she is present to supervise them. After Selina's interview, Arata requests that they teach him magic, which Lilith willingly agrees. However, Selina and Levi note that she will concede to any situation involving education, fantasizing an erotic scene between Lilith and Arata, much to her chagrin. Nonetheless, Arata questions Lilith about his grimoire which she reveals is the Astil Manuscript, a legendary grimoire possessing knowledge from another world. Lilith then continues to explain the concept of Thema, a theme each mage researches from the Archives of the Seven Deadly Sins. However, a blackout suddenly occurs eventually resulting in Arata in a promiscuous position with the girls. While the Astil Manuscript provides lighting, the group discover themselves sealed within a barrier inside the room. Despite being aware of the means to escape, Astil decides to allow the group to discover the exit while she sleeps. As such, Arata then attempts to brute force the door with a chair with no effect to the girls' shock. But they quickly realize his intentions to act without reason due to the principles of magic. Next, the group discuss the culprit's motive which they assume is determining Arata's strength. Although he can already guess the identity of the perpetrator but nevertheless decides to follow along.

Outside, Arin, along with another person, observes the situation from the top of a roof.

The group searches the room for awhile, but they do not discover any clues to escaping. Although Arata suggest they rest, Selina and Levi state the lack of a bathroom as a problem. Unfortunately, they discover Lilith quickly needing to use the bathroom before the other girls eventually find themselves in the same situation. With no remaining choices left, Arata decides to consult Astil, only to learn the grimoire is half-asleep. As a result, Arata, Levi and Selina decide to take advantage of her state to deceive the grimoire into believing they discovered the solution, causing Astil to inadvertently reveal the source under the bed. After destroying the magic source under the bed, the barrier disappears and allowing the girls to escape to the bathroom. The Astil Manuscript is amused by Arata's ploy, becoming eager to see which Thema he will choose. While Arata is unaware of the concept of a Thema, Arin arrives to explain that a Thema is a subject of research a mages dedicate their lives to which allows them to use magic. Noting her timing, Arata assumes that she was the culprit behind the barrier which Arin admits. Despite her actions, Arata remarks that he is not upset since he was able to witness the girls desperation to urinate, but becomes perplexed when Arin offers to do the same. The Astil Manuscript then comments that Arata becomes unstable when interacting with Arin due to her similar appearance with Hijiri before becoming acquainted with her. As the two becomes friends, Arata questions Arin the reason for sealing his room. Arin responds that he is the Demon Lord Candidate, much to his confusion, as stated by the Headmaster before Master Biblia suddenly appears from a window. As such, the two decide ignore the Headmaster and continue their conversation elsewhere to Biblia's disbelief.

In the infirmary, Arata and Lilith resume their questioning about Arin's motive. Arin explains that Master Biblia stated that if the Demon Lord Candidate was put in a stressful situation, another Breakdown Phenomenon may occur. Arata decides to punish the Headmaster, but Lilith had already done the deed.

Meanwhile, a bounded Headmaster panics inside a burning furnace.

While Lilith is curious about the Breakdown Phenomenon, Arin chooses to explain by transforming into her Magus Mode and causing Arata's magic to become unstable removing after removing the Astil Manuscript's seals on his magic. As a result, a Breakdown Phenomenon occurs, but Arin remains insistent on continuing the experiment for the sake of her research. Although, she did not expect the effects to be so powerful.

Elsewhere, Selina meets with Levi who reveals that a Breakdown Phenomenon is occurring.

Outside the academy, Master Biblia is amused by Arin's actions, but cannot allow the school to disappear.

As Arata's magic continually becomes berserk, Lilith decides to intervene but Arin refuses to allow her in spite of the outcome. However, Akio and Mira suddenly appear after completing their latest mission. Mira uses her magic from the Superbia Archive to neutralize the Breakdown Phenomenon while paralyzing Arin and Lilith's movements to allow Akio the chance to eliminate Arata. Akio apologizes to Arata before dealing the final strike.

Characters

 * Arata Kasuga
 * Arin Kannazuki
 * Lilith Asami
 * Selina Sherlock
 * Astil Manuscript


 * Levi Kazama
 * Master Biblia
 * Mira Yamana
 * Akio Fudo

Adaptation

 * Night Lesson & Prison Lock


 * Grimoire Security & Abort

Alterations

 * Arin following Arata occurred after she trapped him, along with Lilith, Selina and Levi, in his room.
 * The issue of the lack of bathroom was first mentioned by Arata before smashing the chair.
 * Arata never expressed his gratitude to Arin for entrapping him within the barrier nor did she offer to urinate for him.

Trivia

 * On October 14, manga artist Nao Akinari and the official anime Twitter account released illustrations of Lilith in celebration of the episode.