Nagisa Shiota from the anime series Assassination Classroom does not marry anyone in the original storyline. The series focuses on his journey as a student and his relationship with his classmates and teacher, Koro-sensei. While there are some romantic hints between Nagisa and his classmate, Karma Akabane, their relationship is primarily platonic and their interactions are primarily focused on their friendship and their shared goal of assassinating Koro-sensei.
The series does not explicitly explore the romantic futures of the characters after graduation.
