Rentaro locks eyes with another soulmate: a beautiful girl in the Chemistry Lab. But when he visits the lab the next day, he instead finds a pint-sized bundle of energy who is... obsessed with drugs?
So she's a senpai and really 
the girl from yesterday...
إذاً هي سينباي والفتاة الّتي
...رأيتُها في الأمس فعلاً
Então ela é minha senpai
e é a garota de ontem...
Получается, она старшеклассница
и та самая девушка…