Why do he keep randomly calling me like a weirdo?

He’s younger than me and we’re friends with benefits. He’s always broke, unreliable, not that cute and his dick is small which is enough of a reason for me to cut him off. To make him understand this and leave me alone I texted him how I felt.. his dick is small etc. He was offended and went off but I didn’t care as long as he got a life and left me alone. Long story short even after everything he STILL reached out to me again and I’m thinking wtf is this man actually a retard or psychotic loser? Cause nobody normal would keep chasing a person who doesn’t want him.
I can’t change my number unfortunately right now just don’t want him contacting me. Help. 😫
Why do he keep randomly calling me like a weirdo?
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