They added some new shots into the OP that includes the recently introduced characters (Marin, Rika).
Coming home from the supermarket, a sick Haruo opens the front door and is surrounded by smoke. When it clears, he sees a person in a hazard suit aim a gun and start to fire at him. After his sisters come home and investigate, Fuyuno figures out from the special bullets that the person inside must also be a mage. The girls knock Haruo out and try to take out the person inside, but get pinned down under the rain of bullets. They counter with their own guns, but they have horrible aim so the person gets away. While chasing after this “killer,” Fuyuno and Chiaki both fall into traps (food and money), leaving Maika alone. Haruo, on the other hand, wakes up in his room with the “killer” who is actually a girl underneath the suit. She tells him not to resist and then steals a kiss. Maika bursts into the room and goes berserk after seeing her brother in a vegetable state. Although Maika lands a hit, the mysterious girl overwhelms her with magic. The only thing that saves Maika from a giant blast is Ayumi arriving home. The girl rushes downstairs and shows Ayumi the cage full of mice that she’s captured. She introduces herself as Anju Rika and the reason she’s been attacking them is to collect data. Moreover, she’s now going to be their new maid in support of Ayumi. The girl’s attention gets diverted from Rika to Haruo when he falls over from being sick.
The doctor gives a grim diagnosis of Haruo having magic fever and the girls all get worried. However, Haruo is completely fine the next day. After sending the sisters home, Rika gets confronted by Ayumi. She figures out that her father sent the new maid, and wants Rika not to interfere with Haruo. Since Rika refuses, the two decide to make a competition out of who Haruo chooses to take care of him. Of course, Rika out-performs Ayumi so the competition turns violent until Rika uses an eel. But after seeing Haruo call out to Ayumi, Rika leaves them alone. Her next plan has her sending letters to both Yuri and Marin. Those two girls come and interrupt right before Ayumi gives Haruo a kiss. However, part of the hospital suddenly explodes and the three are faced with a bigger problem. Rika tells them that the dead spirit of the hospital, called a Paidene, has gotten out. Even though the three cooperate, their attacks do little to the monster. When the Paidene turns around and goes after Haruo, Marin leads the others to putting their lives on the line to block the way. They brace for the impact that never comes because, as Rika tells them, the spirit was summoned in order to test their combat abilities.
At the very beginning of the ED, a few still shots of the characters were added.
Just what this series needs, another magic using girl; a maid no less. They’ve introduced pretty much all of the characters now, so there shouldn’t be anyone new for a while. Past what was introduced in the first episode, Rika brings the first signs of an actual story that involves Ayumi’s family and the teacher at their school. But for now all we’re getting is hints that there’s something at work. With a series like this, I don’t expect much of a back-story, just more craziness and comedy.
Next week, the sports festival episode.