(A Your Lie in April x Harry Potter crossover) Alternate Universe. Takahiko Arima, Kousei Arima's father and the fifth Marauder take Harry Potter and become his father and guardian figure after James and Lily Potter's murder. Little the Arimas, one of the prominent pureblood family of Magical Britain despite their foreign origin, know what the implications of their decision will be.. How well Arima Kousei will be as a sibling figure to Harry? How well the family and their friends will be in showing Harry a meaning of love, especially with magic and music? And how they show Hogwarts the importance of unity? And will they thrive there? This is their story. Notes and Warnings: - Harry Potter and Your Lie in April aren't mine! - Main pairings: Harry x Ginny, Ron x Hermione, and Kousei x Kaori - There will be OOC, and a lot of OC, mostly magicals.