Just a serial murderer

Jaxyne Kayoz was just a 'normal' little girl, she is in first year high school, getting good grades, not the highest, but in the average. One day, in her dorm room, she heard a rumor that one of the students in her school, got murdered inside the dormitory, all of suspects were a male student, and all of the person in the dormitory.

The Suspects are:
1)Dennis Wolf
2)Jaxyne Kayoz
3)Anna Kennedy
4)Trisha Quinn
5)Jamila Moore
6)Olivia Hill
7)Zoe Coleman
8)Margarette Mendoza
9)Judith Schmidt
10)Paula Perkins
11)Chelsie Mays
12)Jillian Vargas
13)Irène Tremblay
14)Donna Lynch
15)Chloe Salazar
16)Abigail Gilbert
17)Amy Williamson
18)Paulette Schneider
19)Ruby Lutz
20)Del Vang
21)Agnes Odom
22)Astra Archier

One of these people is the serial murderer and the murderer will still go on until the murderer is still on the loose.