Torako

Yuuta Togashi suffered from chuunibyou while he was in middle school. When he graduated, he put that dark history behind him and forgot about it... or he was supposed to. High school was smooth sailing and full of enjoyment--until the unavoidable, sad event occurs. The event that locks Yuuta into a contract with Rikka Takanashi and disrupts his desperately ordinary life. (myanimelist.net)

Summary of the first season of the show, as seen from Rikka's perspective with new elements. (myanimelist.net)

Yuuta and Rikka are in their third year of high school. One day in Spring, Touka declares that she will take Rikka to Italy with her, as her job has stabilized there and thinks they should migrate together as a family. Touka is also worried about Rikka not being competent enough to advance to universities in Japan. The gangs from the club suggested Yuuta, who doesn’t want to be separated, to elope with Rikka!! A runaway drama throughout Japan begins. (letterboxd.com)