Based on the manga by Inoue Noriyoshi, which has also had a Super Famicom game spinoff. Natsume Kiroemon, the protagonist, was the 45th leader of the Natsume family, and inherit the Kiryuu no Mimi , a tool which gave its bearer easy access to wealth and women. As a result of his father's death, he left the Italian monastery where he'd been training and rightfully took the name Natsume Kiroemon as well as the power of the Kiryuu no Mimi. Upon his return to Japan, he fell fatally in love with Kanako, one of the members of the rival Mina family. However, the evil hand of the Mina family attacked Natsume constantly and abducted Kanako. Now Natsume has unlocked the seal, making the Kiryuu's power surge, and he's striking back at the Mina family. (Source: AniDB)

The virtual world inside the scub coral (intelligent coral-like lifeforms) created by Eureka... The people from that virtual world appeared on Earth ten years ago when it collapsed. Since this large-scale amalgamation, the humans from the virtual world call themselves Green Earth and the original Earth humans call themselves Blue Earth, and they've come to cause various conflicts with each other repeatedly below the surface. Eventually, Dewey Novak, a senior officer in the Green Earth Armed Forces, rises together with his comrades and finally sets a large-scale terrorism plan into action in order to protect their own dignity. Meanwhile, Eureka, who is detested by the world as the main cause of the chaos, has become a high-grade combatant with the UN's A.C.I.D. unit. Live in order to keep this world at peace... This was the path of atonement she chose. One day, she receives an order to protect a girl named Iris, a new Eureka who has the ability to control scab coral. They fight a lot at first but gradually come to understand each other through their lonely escape. Soon the world faces a crisis, and when that happens, Eureka draws on every last ounce of her strength as she fights. I want to protect Iris and this world. What future awaits her at the end of that wish of hers? (Source: Crunchyroll)

Due to a mysterious disease, the genius Iria Akagami has been forced by her family to stay in a mansion on the isolated Wet Crow's Feather Island with only a handful of maids. To keep herself entertained, Iria invites a variety of fellow geniuses to stay as guests in her home, including computer savant Tomo Kunagisa and her unnamed assistant, skilled fortune-teller Maki Himena, famous artist Kanami Ibuki, academic scholar Akane Sonoyama, and renowned cook Yayoi Sashirono. These visits progress as normal until one of the guests is found gruesomely murdered in the night without a single clue as to the identity of the killer or a possible motive. Tensions rise between those on the island as the killer remains at large, and Tomo's assistant takes it upon himself to uncover the culprit's identity before the murderous events progress any further.

In 2039, helper androids are widespread as general purpose electronics. Keiichiro lost his family in a traffic accident and retired from his band. One day, he finds an android of an old model in a garbage dump. He takes her home, but after taking her to a repair shop he was told that she couldn't be repaired, so he plans to throw her away. The next day, Keiichiro finds her making breakfast for him. Thus begin the summer days of an android with no memories and a dreamless boy.