While Tessa is overseeing the Tuatha de Danaan’s repairs, Mardukas suggests that she take a vacation since it’ll take a long time for the sub to be repaired. At first he offers his full support of any decision she makes, but when he hears her desired destination he strongly protests and Tessa has to hold him to his word. At Jindai High, Sousuke is finishing up a report he’s typing when Kyoko runs in and informs him and Chidori that a masher walked into the girl’s locker room. Sousuke pulls out his gun and runs out to find him with Chidori close behind. Sousuke finds the suspect and throws him to the ground, but to his horror discovers that it’s Mardukas. Mardukas informs them that he came here posing as a Cambridge professor and an acquaintance of Sousuke’s listed guardian Kalinin in order to inspect the school grounds. After a short tour in which Mardukas scolds Sousuke for his poor performance, they return to Sousuke’s safe house. Mardukas doesn’t like it as well and orders Sousuke to clean it up, which takes all night to do. Sousuke asks Mardukas why he had him do this and his answer comes when Tessa appears at his door in civilian clothes. She intends to spend some time studying in Sousuke’s school. While she prepares for school, Mardukas explains the situation and not so subtly warns Sousuke that if anything should happen to Tessa before Mao arrives to assist he will kill him very painfully.
Tessa is transferred to Sousuke’s class and is an instant hit with both the guys and the girls, much to Chidori’s surprise. The teacher informs them that Tessa will only be here for two weeks and warns Sousuke not to display his usual behavior around her. Sousuke now becomes quite stressed as he’s forced to keep watch over Tessa wherever she goes. Chidori and Tessa of course hide the fact that they know each other and get acquainted, but not without exchanging some veiled trash talk. At swimming class, instead of wearing the school’s standard white and orange one-piece, Tessa shows up wearing an old-style indigo one-piece under instructions from Weber. Tessa dives in and stays underwater for a long time. Everyone thinks that she drowned and a panicked Sousuke jumps after her, making a painful full body splash. Tessa emerges at the other side unharmed, and the rest pull Sousuke out of the pool. Tessa tries to steal a kiss from Sousuke by pretending to perform CPR on him, but Chidori stops her and points out that Sousuke is alright. Everyone starts to get suspicious about Tessa’s behavior towards Sousuke and the former makes up a story about them being childhood friends. When Sousuke comes to Kyoko asks him about his relation with Tessa, and his vague confirmation of it causes everyone except Chidori to break out in cheers. Sousuke contacts Kalinin, who’s in the middle of supervising a training exercise, and complains that the stress is killing him. Kalinin assures him that Mao will arrive this evening and to hold out until then. Unfortunately, Mao calls and announces that she’ll be running late because a typhoon blocked all transportation to Tokyo, which means that Sousuke must spend a night alone with Tessa. Mao tells him that it’s his chance to make a move on Tessa and gives him her blessing. Sousuke tries to ask Chidori to spend the night with them, but she refuses out of spite. Unable to hold out any longer, Sousuke collapses. This is reported to Mardukas, who voices his dissatisfaction with Sousuke while Kalinin silently urges Sousuke to not die. Meanwhile, Tessa and Chidori fight over who gets to take care of Sousuke.
After a ten episode absence, the crew of the Tuatha de Danaan finally makes a proper appearance, except for Weber who only appears in a hilarious flashback giving a flashy presentation about school swimsuits. Tessa does everything in her power to get close to Sousuke, and one can only guess what crazy stunts she might pull on him in the safe house had the poor guy not fallen unconscious. I normally don’t take pleasure in watching people suffer, but it’s hard to not laugh when you see all the horrible odds stacked against Sousuke. Too bad that I can’t say the same about Chidori acting like an A-grade moron who still can’t properly interpret anything Sousuke says.