Masaki Yoshida (吉田 茉咲 Yoshida Masaki?) is Tomoko's second and third year classmate in high school. She has become a prominent character since chapter 72, where they officially meet for the school trip to Kyoto.
Yoshida is Tomoko's classmate who has a scary appearance and is often referred to as a delinquent by Tomoko. She often acts violent towards Tomoko when she goes too far, but also likes cute things.
Unlike many of the other girls, Yoshida is quick to anger and extremely violent. During the class trip, Yoshida threatens Tomoko when provoked by Tomoko's characterization of her as a delinquent, and she has even physically attacked her on several occasions usually due to a comic misunderstanding. To be fair, Tomoko is not the only one who views her as rough. When Ucchi later offers her a treat from a vacation trip, Yoshida initially yells at her and refuses, then, when trying it, finds the treat "fucking awesome!" to Ucchi's shock. Yoshida does not seem to care much about school as she is seen sleeping during class and not showing up at all two days in a row.
She does seem to get along with her own group of friends. Her friends, however, do not appear to fear or respect her as Tomoko, Ucchi, and others do. Yoshida displays a bit of innocence which Tomoko and others politely ignore when she does not recognize a "Love Hotel." Her friends freely call her a "moron" to her face which Tomoko and others would never dare to do, and Yoshida never physically lashes out at them. This behavior from her friends may seem to depress her a bit.
Yoshida has shoulder-length bleached hair with dark roots. She is lean and of above average height, being taller than an upperclassman, Megumi Imae. Unlike many of the girls in her class, she has sharp, angled eyes and small irides.
Strikethrough episodes or chapters indicate the character was mentioned but did not make a physical appearance)
Yoshida's relationship with Tomoko is very strained due to a misunderstanding during their school trip where Tomoko mistakenly gropes Yoshida by ticking her while trying to wake her up. She also deeply resents Tomoko treating her as a delinquent. She slaps and punches Tomoko a few times, the first when Tomoko wakes her. However, other cases tend to be comic misunderstandings, such as when Tomoko later reaches behind herself without looking to open a bathroom door only to have Yoshida open it as she is leaving and Tomoko grab Yoshida between her legs. In another, Ucchi tries to wake her and gets a little experimental with her fondling which Yoshida dreams is Tomoko fondling her! Nevertheless, she and Tomoko do seem to care about each other. During the trip, Tomoko notices that Yoshida likes high views to which she asks if it is because, being a delinquent, Yoshida likes to look down on people. Tomoko baits Yoshida to complete a climb for the view. During the climb, when Tomoko sprains her ankle, Yoshida elects to carry her on her back. Imae notices this friendship; though Yoshida denies it.
- Although she's the kind to resort to violence if angered (as seen countless times since she became an important character), she clearly does not hit hard enough to seriously hurt Tomoko, since Tomoko (who is pretty weak) doesn't show any sign of hard pain and bruises after being beaten up by Yoshida.
- Tomoko is convinced she's a delinquent girl, just like a lot of her comrades. It is actually questionable, since despite her look and overall behaviour, Yoshida hates being considered as a delinquent, can be shown getting along with more sober acting comrades and is willing to help them if they are in need. She is brusque and confrontational and swears.
- It is possible she has a job or another source of activity despite still being a high school girl, since she tends to be absent in class.
- She has an affinity for cute things, as seen when Tomoko finds Yoshida's cutesy cat handkerchief.
- Yoshida seems to love Mouseland, but others find her interest in it to be childish and not age-appropriate.
- Yoshida owns a motor scooter (chapter 95).