This is Chapter 7.5 from the Ouran Highschool Host Club Manga series.
Two twins are shown giving a love potion that lasts for two weeks to a girl named Yuri Izumi after Yuri asks them for help in winning the heart of a classmate named Terasaki, upon whom she's had a crush for the last six months. The origin of the matter is shown with Yuri gazing at Terasaki while they're in the library and describing him as really handsome and the only guy who makes her heart beat faster. The twins approach her and ask if she has an "unrequited love," having noticed that she seems to like Terasaki. Yuri reveals the twins' names as Barako Kuronuma and Nadeshiko Kuronuma, known as the mischevious twins at their school. She adds that the twins have something special about them: their ancestors may have been witches. The twins take pity on Yuri and take her into a separate room where they explain that love is a gamble and give her the potion which they claim will make Terasaki fall in love with Yuri, but only for two weeks. After that, fate will decide their future.
Yuri accepts the potion with the twins telling her that Terasaki must drink it. The next day, Yuri is shown with the potion in a cup. She is nervous about things, wondering if it will even work and deciding that just seeing Terasaki's smile will be enough to make her happy. Unexpectedly, a strange blond approaches saying that if she's not going to drink what in the cup, he will. He does so and suddenly asks Yuri if she wants to go out with him. Yuri is shocked and says "What!?" and the stranger introduces himself as Nozomi Tsuruda from Class 2-A (the same class as Yuki), his hobby is music and he has seven piercings.
The following day, Yuri goes to speak with Barako and Nadeshiko, who tell her that she's pathetic. Yuri asks for help since she can't tell if Nozomi is really interested or if it's the potion. The twins remind her that its effects only last for two weeks and Yuri starts crying, wondering if Nozomi might be a scary playboy. Nozomi enters the room and asks Yuri to leave with him; Yuri says she might be awhile but he replies that he'll wait. When they finally go to the library, Yuri notices Terasaki. Tsuruda wonders why Yuri is so quiet and Yuri worries that Tsuruda will think she's the "weak" type. Tsuruda tells her that there are things he wants to tell her, but can't, and so he quits before even trying. Yuri stares at him and Tsuruda asks if he's being too serious and chuckles.Tsuruda and Yuri continue to walk together, Yuri surprised to learn that Tsuruda is a deep person even without having much conversation. They stop by a CD shop and a guy with a lot of tattoos greets Tsuruda. Tsuruda asks if the CD he asked for is there, causing Yuri to think Tsuruda is "scary" because he's talking to a guy with tattoos. The guy looks at Yuri and asks Tsuruda if Yuri is his girlfriend, adding that she's pretty cute. The tatooed guy then talks to Yuri, explaining that while Tsuruda may look like a playboy, he's not. He knows this because one time Tsuruda liked a girl for two years and when he finally asked her to meet him at Shibuya's Tower Record store, he waited for her to show up for six hours. Yuri thinks Tsuruda was stupid to wait that long for a girl to show up. The guy then jokes that he heard Tsuruda locked himself in his room for a month after that. Tsuruda hears him talking and says that the incident was in the past and he doesn't care any more.
Tsuruda and Yuri leave the shop and Yuri hands Tsuruda a book because the day before he'd asked if she knew of any. Yuri tells him that the book is an easy one to read even if she doesn't like the story. Tsuruda replies that it's clear that Yuri put of alot of thought into the matter. They continue hanging out, even though Yuri worries that after two weeks everything will fade away. Nadeshiko sees them hanging out, saying it's fun watching them, while Barako states that it's just the beginning.
Back at home, Yuri's sister asks her if she has her dictionary and finds both the dictionary and a Nirvana album. The next day, Yuri tells Tsuruda she listened to the album, which is the CD Tsuruda bought at the shop the previous day. Tsuruda is shocked that Yuri listened to it and Yuri says she found the music quite nice. Tsuruda asks her why she liked it and says he's happy, which makes him and Yuri blush a bit.
Later, as Yuri is taking a bath and thinking that there's only four more days before the potion fades, she says that she wishes two weeks could last forever. The next day, Yuri talks to Tsuruda and says the next weekend her favorite aoyoma is coming. Tsuruda ask if she knows Joseph Connel and Yuri replies she really likes that person and laughs because finally she's found something they both like. Tsuruda asks Yuri to see him together the following week and Yuri replies, "Maybe," tearing up because she knows the effects of the potion will fade away before then. Tsuruda panics and asks her what's wrong. Yuri says it's nothing, it's just something in her eye. Tsuruda grabs her and says then she should take care of it right away, but Yuri says she can go alone and he agrees. In the bathroom, Yuri thinks of Tsuruda's smile and the conversations they've had because of the potion.Yuri goes to find Barako and Nadeshiko and is surprised when she sees Tsuruda with them. Yuri overhears their conversation and discovers that the love potion didn't work; the twins tricked her. Tsuruda sees Yuri but Yuri runs away. He chases after her and she starts crying because of all the anxiety she's felt was for nothing. While running, she bumps into Terasaki, who says Yuri's the girl who comes to the library daily. Yuri looks at him and Terasaki asks her if the guy she was with the last time he saw her (Tsuruda) is her boyfriend. Yuri replies he's not and Terasaki says Yuri looks like a studious girl and didn't think she'd date someone that dumb. Yuri begins to say that she always thought about Terasaki which Terasaki says he knows; but Yuri interrupts him and states that he's no different than Tsuruda by calling him dumb without knowing him. Then she shouts, "Don't talk like that about the person I like!" Tsuruda approaches and tells Terasaki he's sorry, but Yuri is his girlfriend. Terasaki walks off. Tsuruda hugs Yuri and explains everything: he knew that Yuri went to the library to stare at Tsuruda so he asked the twins for help. He then says he really likes Yuri even without the potion. Barako and Nadeshiko see them and cheer because their plan has worked so well. Tsuruda continues talking to Yuri, saying that the love potion is really quite effective because it allowed him to speak with Yuri freely.