Mamiko Ikeda

Three girls, Umi, Sora, and Ao, run a jack-of-all trades buisiness. They, who accept any job at all, come across their hardest job ever. They must convince a boy, Rikku, to return to school when they dont even go to school themselves. (animenewsnetwork.com)

Dejiko decided to take a vacation and visit her home, Planet Di Gi Charat, together with Puchiko, Gema, and (accidentally) Rabi~en~Rose. However, Piyoko and her aids would not let go this chance to capture her. (animenewsnetwork.com)

Yuusuke Kamoshita who is living alone until one day he stumbles across a naked girl in a forest, a very energetic girl named Noelle, then after she knows him better, she wanted to become his angel.. Noelle and her entire family proceed to move into Yuusuke's very large home and disrupt his life. But as their life goes on, Silky and her minions interfere as the series goes on. (myanimelist.net)

Keroro is a frog-like alien sent from his home planet on a mission to conquer Earth. But when his cover is blown, his battalion abandons him and he ends up in the home of the Hinata family. There, he's forced to do household chores and sleep in a dark basement that was once supposedly a prison cell haunted by the ghost of an innocent girl. He even spends his free time assembling Gundam model kits. (myanimelist.net)

Ikuto Touhohin just had a fight with his old man, one that led him to make a rash decision to run away from home. He boards a ship, deciding to take a vacation, but the ship is suddenly hit by a huge storm--one that sends Ikuto overboard! When he regains consciousness, he realizes he is still alive on some island. An isolated island. An isolated island with nothing but girls. Beautiful girls. (myanimelist.net)

Hashiba has an accident and has lost all of his memories. When Fujimori comes to his school as his new roommate, He tells Hashiba that he is called Ran. He and Hashiba both have a split personality which they developed in their youth. (imdb)