Taking place after the events that occurred in Hayate no Gotoku! Can't Take My Eyes off You. Hayate, Nagi and Maria return to their daily lives at the Sanzenin Mansion and the Violet Mansion. (Source: Hayate no Gotoku! Wikia)

Taking place one month after the events that occurred in the movie Heaven is a Place on Earth. Living at the Sanzenin Mansion once again, Nagi returns to her old ways of life, until she receives word from American authorities informing her that she has a week to pick up her late father's belongings that was indefinitely delayed due to various circumstances. After receiving news of her father whom she doesn't remember, Nagi then meets a mysterious girl (with a hidden agenda) claiming to be Nagi's little sister. The series tells a new story that is original to the anime and not directly based on the manga. The main author of the original series Kenjiro Hata personally created the original concept for the story of this anime. (Source: Hayate no Gotoku! Wikia)

For some people, high school represents the opportunity for a fresh start. You can take new classes and make new friends. For Souichiro Nagi and Bob Makihara, though, high school means something different: the chance to become the top fighters in the entire student body! Too bad Toudou Academy is the hardest possible place to realize their dreams. Their new high school is no ordinary academic institution. Rather than concentrating on classic subjects like math and science, Toudou Academy was created for the sole purpose of reviving the martial arts in Japan! As a result, Souichiro's aspirations to become top dog are cut short when he runs afoul of Masataka Takayanagi and Maya Natsume. The two upperclassmen easily stop the freshmen duo's rampage across school, but rather than serving as a deterrent, it only stokes their competitive fire. What kind of monstrous fighters attend Toudou Academy? Are there any stronger than Masataka and Maya? And why in the world is Maya's younger sister stalking Souichiro? Learn the answers to these questions and more in Tenjou Tenge!

In California's Center City, shy but kindhearted Joseph Carter "Joey" Jones lives with his grandmother, working in a coffee shop. Though his family is financially burdened and he is bullied at school, he remains cheerful. A robotics enthusiast, he wants a top-of-the-line toy robot called a Heybo more than anything. One day Joey and his friend Simon "Psy" Kaina come across a destroyed Heybo discarded by a group of rich kids. He takes it home and repairs it himself, excitedly naming it Heroman. However, one night Heroman is struck by lightning and comes to life, growing several times its size in the process. That same night Center City is attacked by aliens called Skrugg whose attention was brought to Earth after Joey's acquaintance Professor Matthew Denton made attempts to contact them. Along with Joey, Heroman quickly heads to the scene of the attack, where he finds people in trouble, including his friend Lina Davis and her father. Using an arm-mounted controller, Joey is able to command Heroman to use superpowers to fight off the Skrugg and rescue civilians. As the aliens continue their invasion of Earth, the duo are the only ones separating humanity and destruction. [Written by MAL Rewrite]