If you're looking for manga similar to Da Capo: Plus Communication (Light Novel), you might like these titles.
Takeru and Sumika have been neighbors and friends since they were little, but when a mysterious girl arrives, and is found in bed with Takeru, their daily lives will be thrown into chaos.
There is a world which is divided into the heaven region and the devil region. Baal is the man who leads the army of the devil region and tries to fight the heaven region. But his ambition is soon destroyed.... He is confined for 100 years and all his memories are erased. He is now released, but there is no job to take.... But one day, he is recruited as a teacher at a magic school in the heaven region. He jumps at the chance and decides to work there. In his class, there are a lot of dropout students. He takes in charge of three students and works hard! Days later, his ex-coworkers suddenly appear from the devil region and the atmosphere of the heaven region gradually becomes uneasy...
For Aizawa Yuuichi, returning to the town where he spent his childhood has been an unusual affair. Yuuichi, it seems, has forgotten his memories of the past, including encounters with several young ladies who would love nothing more than to see him again. As the days pass, flickers of the past began to surface, revealing more and more of the dark events that once came to be. As the reuniting continues, Yuuichi soon starts to realize that his past may be far more complex than he once believed it to be...