It is a cross over between the series Lupin III and Detective Conan and takes place after the television special Lupin the 3rd vs Detective Conan. The plot follows Conan Edogawa who sets out to apprehend Arsène Lupin III, the suspect of stealing a jewel called Cherry Sapphire.

(Souce: Wikipedia)

After a successful showdown at Tokyo Tower, the Mew Mew girls enjoy a temporary respite. Now that Ichigo Momomiya and Masaya Aoyama have confessed their feelings to each other, Ichigo is overjoyed to spend time with her new boyfriend. However, their quick break gets interrupted, and soon the girls must battle against the Chimera Anima yet again. When things go awry in the ensuing fight, Ichigo is placed in grave danger. Just when things look most bleak, the mysterious Blue Knight arrives and saves Ichigo, proclaiming that he was born to protect her, before disappearing into thin air. With the fate of the world on their shoulders and the identity of the Blue Knight in question, the Mew Mew girls must strive to create balance between alien-fighting and their personal lives.

After solving the incident of the scattered Jewel Seeds, Nanoha Takamachi happily returns to her everyday life, though now with added magic practice in the morning. Exchanging video messages with Fate Testarossa and the crew of the Arthra, Nanoha eagerly awaits the chance to speak with them in person again. But while studying in her room one day, Raising Heart suddenly calls out to Nanoha and warns her of an incoming attack! The attacker is a young girl named Vita, who calls herself a Belka Knight. She proves her strength by using an intelligent device with a mysterious cartridge system to quickly overwhelm Nanoha. Luckily, the Space-Time Administration Bureau is able to step in before she is completely crushed. Vita and her fellow knights Shamal, Signum, and Zafila are on a mission to steal magical power from mages in order to complete the Book of Darkness, one of the Lost Logia. For what sinister purpose are the knights after this Book of Darkness? [Written by MAL Rewrite]

A parody series featuring the entire cast of The Melancholy of Haruhi Suzumiya in a smaller form factor. Among the changes are: Yuki plays eroge, Haruhi is even more obnoxiuous and loud, Mikuru is even more emotional and Koizumi harbors a deep love for Kyon. Kyon, on the other hand, is generally the same as ever.