|“||Yamai-san is aggressive||”|
|Full Name||Yamai Ren|
|Age||15 (first appearance)|
|Affiliation||Komi Shouko (crush/obsession)|
|School||Itan Private High School|
|Manga Debut||Chapter 5|
|Anime Debut||Episode 2|
|English Voice||Cristina Vee|
|Japanese Voice||Rina Hidaka|
Ren Yamai (
Ren sports a long auburn hair with flyaways at the end and bangs adorned with a red ribbon over her left ear. Yamai wears the Itan Private High School uniform on school days and dresses in a more girly fashion on off days.
Underneath her cute facade, Yamai is obsessed with Komi to a disturbing degree, ranging from stalking her to lustfully licking a strand of her hair. She has been described as a yandere. Ren even has a collection of pictures of Komi in her room. In her introductory arc, Ren resents Tadano for befriending Komi with little effort and kidnaps him, believing that she was doing Komi a favor due to viewing him as completely average. However, this ends up blowing up in her face when she saw that the opposite happened with Komi wordlessly telling her that she would decide on her friends herself.
After the incident, Yamai tones herself down instead of resorting to situations where she could act pervertedly around Komi. One instance is when she attended the summer festival and wanted Komi to kneel down so she could take a bite from her sausage only for that to be thwarted by Najimi.
*Entering spoiler territory for chapter 302 of the manga*
Upon learning about Komi dating Tadano, her immediate instinct was to kill him but relents when Komi throws herself in front of him. After taking a leave of absence from school for a few days; Yamai resigns herself to being an observer since if she attempted to sabotage Komi's relationship with Tadano, this would only result in her being even more distant from her. Even then, Chapter 312 makes it clear that she would wait for the hype to die down and then orchestrate Komi and Tadano's breakup and she would swoop in and take Komi for herself.
Ironically, the love Yamai has for Komi is genuine, but her fatal flaw causes her to become alienated. In the aforementioned Chapter 312, when she learns that Komi was coming over, she makes her tea, but contemplates adding "Sleepy Sleepy Time" sleeping pills to it only to be prevented from doing so by her friends. In fact, Yamai has the habit of making her plans of being closer to Komi fail. When Tadano first meets her, he was actually going to suggest she be friends with Komi, but instead, she gets grossly offended by the casual way Tadano brought up Komi in the conversation. Additionally because of her low opinion of Tadano, as well as her perverted behavior in general, while she is tolerated, anything that equates to Yamai taking her relationship with Komi deeper is null.
Ren is a leader of the girl's group in Class-1 and, like the whole student body, a member of Shouko's entourage. She calls Shouko "Komi-sama" and secretly worships her to a greater degree, even than the rest of Itan High. Ren shows a violent and conniving true side of herself when someone she sees as unimportant grows close with Shouko, namely Hitohito. Despite her initial scheme against Hitohito and Shouko's rejection of her advances, as a result, Ren learned to tolerate Hitohito and managed to tone down her insanity enough to become one of Shouko's companions. Still, throughout the story, she has attempted various tactics to catch a glimpse of Komi's underwear or take a panty shot, touch her boobs or otherwise feel her up, be touched by her, etc.
As a second-year at Itan High, Ren is shown to have made friends with Manbagi Rumiko's friends, the gyarus, in her class.
- The name やまい れん (Yamai Ren), is written with the characters for mountain and well but can also be written as 病 to mean illness, which the word yandere came from. れん (Ren) is an alternate reading of 恋 (koi) ,which means love.
- She claims that she doesn't get along with Nakanaka Omoharu (and vice versa), but the two have a notable rivalry for Shouko's attention that causes them to repeatedly be seen acting in sync. (Their classmate Sukida Lily ships "Naka x Yama," often appearing when they bicker.)
- Her idea for the Cultural Festival was the Haunted House, her ulterior motive being getting away with touching Shouko's butt under the cover of a dark classroom.
- Ren is a rather materialistic person; she spends her breaks on luxurious vacations and likes designer clothes and accessories. This suggests that (like the archetypal popular girl) she comes from a wealthy background.
- Ren is among many a very hateful third wheel in everything and does not care about others' opinions as in believing that her own opinion is the right one.
- Ren is voted as the most hated character in the manga and show.