Mamoru Itsuki
Itsuki mamoru
Vital statistics
Title Mamoru Itsuki
Gender Male
Race Japanese
Age 20
Abilities Sightjacking
Weapon Scantling
Iron Pipe
Fire Poker
Monkey Wrench
9mm Handgun
Annaki Remains (Horn)
Allies Yuri Kishida (through manipulation)
Ikuko Kifune
Yorito Nagai
Voiced by Takumi Saito

Mamoru Itsuki (一樹 守 Itsuki Mamoru?) is the main character in Forbidden Siren 2. A magazine reporter, he investigates the island Yamijima for an article after getting permission from his editors to do so. The boat ride to the island ends in disaster, as it crashes in the middle of the ocean. Waking up, he soon finds a companion, though he fails to realise that he is a pawn in a deadly game.


In the game, Itsuki has the image of being incredibly interested in the occult and occasionally running wild, but in actuality he is a perfectly sane and completely normal young man interested in modern literary arts. Having got a part-time job at the editing department of Atlantis, his favourite magazine since he was a child, Itsuki pursues his hobby at work, and gets the chance to work on books, which has been his dream more than anything else, and works as hard as he can in the editing department. His passion is acknowledged by his boss, and he takes a job at Super Scientific Research Co. upon graduating from a specialist school (the company generally only hires employees who have graduated from university, so he is a special case). However, though he performs well at his job he has no real-world experience to prove himself as a journalist in things such as setting up his own plans and collecting info or articles. Feeling that neither he or the editor-in-chief will accept him if he simply sits behind a desk, and believing he should be doing more, when called to a meeting he makes unreasonable demands, such as asking to be allowed to go and conduct research in Egypt (for which they actually did not have the money), and running wild due to his youth (of course, his youthful drive endears him to his superiors).

Having removed the seals on the "seven gates" and making the descent to the Netherworld, Itsuki is saved by Ikuko as he is about to be sucked in by Mother, and realises that he has been used by Yuri. He takes responsibility for this by destroying the seven stone markers, although he realises that it will do nothing to help the situation and feels an intense sense of blame (naturally, since Mikami and Abe also made the descent together it wasn't just Itsuki's fault). Reaching his physical limits and mentally exhausted he almost gives up, but as he learns the true nature of the Yamirei and Shiryo as he wanders the island (that they are monsters that are weak to light, and can be defeated), he gradually begins to fill with anger towards the one who made this happen. Through meeting Yorito Nagai, a comrade from the same world as him, and Ikuko Kifune, a girl with strange abilities, he regains his strength and uses his unique, characteristic point of view (reasoning) to end the strange events.


Mamoru is a person who looks at things from a logical perspective, thinking of how to explain supernatural things in a down-to-earth view. However, as he faces the creatures on the island, he accepts the situation he is in. 

Another, less noticeable part of Mamoru's personality is that he is literal-minded. In a talk with Ikuko at the docks before going to Yamijima, he takes a joke Ikuko makes about swimming to the island literally, even calculating the distance of the island and wind direction. 

After releasing Mother, Mamoru is filled with anger towards her, Yamirei and Yamibito, as well as guilt for being fooled by Yuri to begin with. When he enters the Bright Win, he wishes to eradicate every Yamirei he can find, calling them "Beasts from hell".





Mission 1

Mission 2



Yamijima Harbour/Dolphin Pier

Reach the road to Uryuga Forest with Travelling Companion

Find medal



Yamijima Island/Uryuga Forest

Read the road to Hidaru with Yuri Kishida

Acquire hair ornament



Yamijima Amusement Park/Coffee Cup Ride

Reach the Fate to the Underworld

Acquire a glimpse of Mother



Bright Win/Forward Deck

Defeat Tomoe Ohta

Annihilate Yamirei and Yamibito


Mad Laughter

Shinari Mountain/Pylon #4

Destroy Tomoe Ohta

Reach the top of the tower with Ikuko Kifune



Shinari Mountain/Pylon #4

Defeat Mother




Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.