The third season of Date A Live. 
 
Itsuka Shidou's life has been a whirlwind as of late. Or more precisely, a spatial quake. Several of them, in fact. Powerful "Spirits" from other dimensions that take the form of girls are unintentionally causing these spatial quakes in his reality. And Shidou is the only one who can stop them with his unique ability: kissing them! By having the girls kiss and fall deeply in love with him, their devastating quake powers are sealed. The alternative to romancing them is to have a more militant and technological organization called the AST (Anti-Spirit Team) destroy the Spirits, something Shidou is vehemently against.
 
So far in the story, six Spirits have fallen for Shidou (as well as a few others). The girls compete with one another and vie for his affection, leaving him no end of headaches and misadventures. But a new challenger approaches.
 
(Source: Tokyo Otaku Mode)

Set in the premise after the events of Date a Live II, a mysterious existence named Mayuri has started to appear in Tengu City. Shidou set on a date to figure and find out the identity of the spirit. In order to find out the reason of the interruption of the disturbance that occurred, he goes on a date with six of the spirits that wanted him all for themselves for the mysterious being to appear. 
 
Note: An original story supervised by the original light novel author Koushi Tachibana.

Shidou Itsuka has a problem. The world has been racked by massive quakes of an unknown source for years now, though life goes on. Then one day, Shidou's calm life ends forever when in the middle of a quake in his city, he meets a girl who's apparently a spirit-and the cause of all the destruction! When a team arrives to eliminate the threat, Shidou becomes embroiled in a war to protect these spirits-by making them fall in love with him?! 
 
(Source: Yen Press)

The fourth season of Date A Live. 
 
Despite the numerous challenges he has overcome so far, Shidou Itsuka's mission with Ratatoskr is far from over. In a departure from his daily routine, Shidou encounters a starving woman lying on the street and ends up helping her. After the two arrive at her apartment, the woman introduces herself as Nia Honjou—a popular manga artist working under a pen name. However, cutting straight to the chase, Nia reveals that she is also a Spirit and is aware of Shidou's secret operation. 
 
Interested in seeing his charisma firsthand, Nia challenges Shidou to win her over on a date. As he strives for an opportunity to seal her powers, Shidou learns more about Nia and her history with Deus Ex Machina Industries, a name he is all too familiar with... 
 
(Source: MAL Rewrite)

The first part of Date A Bullet.
 
Hibiki Higoromo, better known as, Empty, is an amnesiac young girl. She wakes up in the neighboring world, where she encounters Tokisaki Kurumi. In order to kill the mysterious girl, Kurumi leads Empty to a school. When arriving at the school, a number of girls, known as semi-spirits, gather together. Now then, a new battle begins. (Source: Wikipedia)

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