Mikado Yaguchi/Relationships

Mr. Yaguchi
Not much is known about Mikado's relationship with her father.

Unnamed Second Oldest Big Sister
Mikado has a great relationship with the middle child of her family. She is the one responsible for inviting Mikado and Kako to the mixer at the start of the series, and is later on shown making Valentine's chocolates with the girls, Yui and Ichika.

Kako Motoya
Kako is Mikado's best friend, and the two are extremely close. Mikado was the first one that Kako was able to tell about her marriage to Kota. In a similar vein, when Mikado noticed that she had feelings for Jiro, the first one she told was Kako. Kako was extremely overjoyed at the prospect, pointing out that she had noticed a change in Mikado's behaviour recently, which had led her to suspect as much.

Jiro Nagakura
Jiro and Mikado share a close, deep bond. They've known each other for most of their lives, and have always treasured each other.

At some point during the summer break of their second year in high school, Mikado notices that her feelings toward Jiro have changed and that she's developed a crush on him. She ponders whether the change had really been so sudden, but leans toward a gradually forward creeping crush, remembering the times when they were still young and she'd thought he'd been cool.

Heisuke Okami
Mikado was rather reluctant in trusting Heisuke ab initio, however, later on, she grows to respect him.

Yui Sendo
Mikado finds herself the butt of Yui's insults just as often as Kako. Despite the harshness of them, she's grown to embrace them, taking her label as "ugly" with stride. She and her sister offer Yui rides home from school, and she even sleeps over at Mikado's place once, which was very tiresome for Yui.

Kota Sagano
Mikado did not like Kota at first, seeing as he had rejected and hurt Kako, and had been an all-around pain for the girls with his constant nagging. However, later on, she seems to get on pretty close terms with him, even if he often asks her armour piercing questions about her love life, which she would rather not reveal to him; such as her crush on Jiro, which she at first desperately tried to hide, and much later on about her reaction to Ryu flirting with her. Both of these incidents led to Kota getting stabbed multiple times by her with a pencil.

Ryu Katsunaga
Mikado was not very impressed by Ryu when they initially met, but she warmed up to him very quickly. He complimented her multiple times, saying things like her name is cute and befitting of her (much to the disdain of Kota, who ironically enough does not want adults flirting with teenagers in his household). Ryu is quick to get her to open up about her crush on Jiro, reassuring her that whoever she had a crush on clearly was not worthy of her attention anyway and that she would find a new man in no time. When he a little bit later finds out that the one she liked was Jiro, he is shocked, at first pointing out that Jiro is nowhere near as good looking as Mikado and then questioning Jiro's logic in rejecting her. He points out that if he was still in high school, he would be "all over her". Kota then proceeds to make the assumption Mikado is his type, which he admits to being true. Later that night Ryu gives Mikado and Jiro a ride home.

Next year for Valentine's Day, Mikado gets roped into making chocolates with Kako, Yui and Ichika, despite having no one to give them to. She originally planned to eat her portion of the chocolates by herself but is convinced by Kako not to. When Valentine's Day finally arrives, she loiters around at the subway, with a plan to give the chocolates to the first person she recognizes in the crowd. She almost gives up, disturbed by the lovey-dovey couples that surround her, but then hears Ryu calling out to her. She hands the chocolates over to him, explaining the situation briefly. Despite the sweets not having any deeper meaning behind them, Ryu is still happy to receive them from "such a cute girl", and offers to walk her home, sharing the chocolates on their way.

Ryu is shown coming to visit Mikado at her workplace in the last chapter of the manga, which leads to Yui assuming the two have been dating since Mikado was still in high school. Mikado denies this, and says she and Ryu had simply met at Kako and Kota's babyshower and exchanged numbers there.