Aika (愛歌 Aika) is a summoner and middleman of Government.[1]


Aika is a girl with light brown hair and brown eyes. She has her hair styled in two long braids, which are then secured into two loops on either side using hair accessories adorned with cat bells. The most striking feature of Aika's appearance is her tendency to exclusively wear a neon green striped two-piece swimsuit.[1]


Aika is a shut-in who idolizes Kyousuke Shiroyama, affectionately calling him "Onii-chan" and often going on delusions about their relationship despite not being siblings, blood-related or otherwise. As a shut-in, she has Kyousuke and her subordinates run errands for her.[1] However, despite being a shut-in she still goes out late at night to go for walks or to bathe in the moonlight with her white liger, which has created a rumor of a girl's ghost roaming the streets looking for the person that threw her into a lion's cage.[2] Despite her shut-in status and using low-ranked 50 Award summoners to run errands for her, Aika is apparently very popular and really liked by them, as she always looks after them, never sacrificing them and tries to act as a buffer with Illegal and Freedom to avoid senseless killing.[3]

According to Kyousuke, Aika became a shut-in after losing hope in the outside world once she reached 100 Awards and everyone not in the summoning business started forgetting about her.[4]

She is very jealous of other girls taking Kyosuke's attention from her, as seen by her rivalry with the older Lu Niang-Lan[1] and her opinion of Olivia Highland, Kyousuke's last vessel prior to the events of the story.[5]


In the past, Aika was in the business of exterminating monsters and sealing ancient texts. She was also antagonistic towards Kyousuke at that point. This, however, changed at the present time, where she maintains feelings of sibling affection towards Kyousuke despite being completely unrelated by blood. Her rivalry with Lu Niang-Lan was also apparently much more vicious, as Kyousuke mentions the two had tried to kill each other in the past.[1]


Light Novel Volume 01Edit

Aika had been asking for Kyousuke's help in tending to her needs, often asking him to do some errands and house chores. While Kyousuke and Lu Niang-Lan were at her apartment, her white liger started to get restless, which Kyousuke revealed was caused by the injured Higan Meinokawa he had brought to the apartment with him. Then Kyousuke announced to Aika and Lu his intention of making one last job as a summoner.[1] After moving Higan to one of the rooms in Aika's apartment, Aika and Kyousuke discussed Guard of Honor, with Higan trying to get Kyousuke's help to find and save her sister Renge after Aika revealed his identity as Freedom Award 902, Alice (with) Rabbit. However, Kyousuke refused to help her.[6] That night Aika called Kyousuke to inform him that Higan hadn't returned to her apartment, and was probably looking for her sister on her own despite not having any power without a summoner, which forced Government to officially consider her an enemy and send their forces after her, including Azalea Magentarain. The two also talked about Olivia Highland, Kyousuke's previous vessel.[5] Aika would later be part of the group's discussions after Renge summoned the White Queen and the White Queen left some shards of herself inside Higan that threatened to kill Higan if Kyousuke didn't defeat the White Queen in time. Aika gave Kyousuke the information Government had gathered on Guard of Honor and Azalea Magentarain.[7]

After Kyousuke defeated the White Queen and saved Higan, Aika talked with him over the phone about how the Meinokawa sisters had received hush money from an unknown source that would save their shrine from debt. She also mentioned the sisters were angry with him for severing the summoner/vessel contract before Meinokawa Higan woke up, and that both would probably start searching for him all over the city.[8]

Light Novel Volume 02 Edit

Aika received a text from Kyousuke, telling her that he and Lu would be arriving soon. Though angry at the fact the older woman would also be there, Aika decided to walk in the rain for a bit to create a see-through effect and grab Kyousuke's attention. However, she was shocked when she found the two gasping for breath, sweating and laying against each other on her couch. Aika demanded an explanation, and when Kyousuke told her he and Lu had been at A Block she got even angrier, having found info online about the block also being a hotel district. She ordered her liger to attack them, but she simply approached Kyousuke and laid on top of him affectionately.[9] After Kyousuke arrived with Ryouko Umie to her apartment Aika once more complained about him bringing other girls to her place, though she agreed to help him and Ryouko after he bribed him with food. She used Packet Atmosphere to visualize the pattern of the Rainy Girl's appearances. She analyzed it, concluding it matched the operation records of a Toy Factory on the outskirts of their city.[10] Later Aika was in her apartment watching a late-night variety show and complaining in a message board while Lu, who was also in the apartment, called Kyousuke to relay the info she had found on Fuuki Benikomichi.[11] After defeating Fuuki and Hayato, Aika was called by Kyousuke, who asked her about the weather map's state. Aika informed him that the abnormal weather patterns were breaking down and that Government had investigated the ruins of the factory and had concluded that the special materials in the atmosphere would not last long-term without the ignition.[12]

Light Novel Volume 03Edit

Aika cooked a meal for Kyousuke after Golden Week ended. While Kyousuke was willing to tolerate the bad taste of the food, he quickly got angry once Aika admitted to having made it taste bad in purpose, as it would be expected from a little sister's homemade food.[13]

Kyousuke would later contact Aika during his mission with Isabelle as he took down the users of Girl's Backdoor. Aika informed him of a summoner and vessel pair starting a summoning battle in A Block, and Kyousuke asked her to track them for him.[14] When Kyousuke learned from Lu about Anthills he tried asking Aika, but she refused to talk about them over the phone and asked him to come to her apartment. Aika revealed to him that the Anthills were a secret Government project to artificially create vessels for their faction.[15] Lu suddenly arrived at the apartment and attacked them, as she was under the influence of Girl's Backdoor. She quickly knocked out Isabelle, Aika and Aika's liger, but Kyousuke managed to set off a trap using the sprinklers and the wiring to knock all of them out.[16] However, upon waking up Kyousuke realized Aika had been controlled through Lu to leak the list of Anthills to the enemy.[17] As Aika and the others tried to decide in a course of action she was suddenly called by a Government coordinator, who wished to discuss Aika's security leak, informing them that the superiors were very angry and were blaming her and her Illegal acquaintance, as they had never liked the apartment were agents of the three world powers gathered in peace. Kyousuke was told that he would have to help Government free of charge with their Anthill evacuation. Kyousuke pointed out the flaws on their plan, and offered to help her convince her superiors to change it.[18]

Light Novel Volume 04Edit

After causing the destruction of Pandemonium and terminating his contract with Mika Himekawa, Kyousuke contacted Aika to inform her of his situation and asked her to have someone pick him up to escape the area. Aika agreed, asking him to return fast since she was getting tired of Lu's Chinese cooking.[19]


Aika is a summoner with 870 Awards known as Hikikomori (専守防衛(HIKIKOMORI) Senshubōei (HIKIKOMORI), lit. "Exclusively Defensive Posture").[13] She's also a middleman of Government, a person who assigns jobs to other summoners. She commands several Award 50 summoners. She seems to be well off, considering she lives in a luxury top-class apartment that takes up two whole floors which have been opened into a single space. In fact, she has also purchased the roof as an open-air park and home garden. Unlike most summoners, she doesn't use a human as a vessel, instead choosing to use a white liger made from crossbreeding a lion and a white tiger, a super-rare species that costs at least 700 million yen a year to rent from the zoo.[1]

As a Blood-Sign, Aika uses magic to transform what appears to be sugar, causing it to melt, lose form, twist, and form a 150cm staff that looks more like a striped stick of candy with vanilla and mint colors.[20]



  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Mitou Shoukan://Blood Sign Volume 01 Opening X-01
  2. Mitou Shoukan://Blood Sign Volume 01 Stage 2 Part 7
  3. Mitou Shoukan://Blood Sign Volume 03 Stage 3 Part 3
  4. Mitou Shoukan://Blood Sign Volume 02 Stage 2 Part 8
  5. 5.0 5.1 Mitou Shoukan://Blood Sign Volume 01 Stage 1 Part 3
  6. Mitou Shoukan://Blood Sign Volume 01 Stage 1 Part 1
  7. Mitou Shoukan://Blood Sign Volume 01 Stage 3
  8. Mitou Shoukan://Blood Sign Volume 01 Ending X-01
  9. Mitou Shoukan://Blood Sign Volume 02 Opening X-01
  10. Mitou Shoukan://Blood Sign Volume 02 Stage 2 Part 9
  11. Mitou Shoukan://Blood Sign Volume 02 Stage 4 Part 2
  12. Mitou Shoukan://Blood Sign Volume 02 Stage 4 Part 7
  13. 13.0 13.1 Mitou Shoukan://Blood Sign Volume 03 Opening X-01
  14. Mitou Shoukan://Blood Sign Volume 03 Stage 2 Part 2
  15. Mitou Shoukan://Blood Sign Volume 03 Stage 2 Part 5
  16. Mitou Shoukan://Blood Sign Volume 03 Stage 2 Part 7
  17. Mitou Shoukan://Blood Sign Volume 03 Stage 2 Part 8
  18. Mitou Shoukan://Blood Sign Volume 03 Stage 3 Part 1
  19. Mitou Shoukan://Blood Sign Volume 04 Ending X-02
  20. Kamijou-san, Two Idiots, Jinnai Shinobu, Gray Pig, and Freedom Award 903, Listen Up! …Fall Asleep and You Die, But Not From the Cold☆ Part 7