Why do students studder around me especially a girl student. Its worrying?

There's a student that stay quiet in class but when she goes to talk to me she shudders not able to get the word out. Whenever she walks up to me she always have her friend with her.

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2 mo
Turns out she had a very strong crush on me…and she’s not graduated and in college.. and also her family got me in trouble and so I just quit because I was tired of bullying and so yeah
Why do students studder around me especially a girl student. Its worrying?
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