the fat troll as you call him, may have romantic feelings for your daughter and knows he cannot win her affection so has opted for the hate me option... trying to get her to feel something for him other than indifference.
does your daughter feel threatened by this schmuck? if so, definitely tell the boy’s father. i would tell him anyway. and tell my daughter to avoid and ignore him.
“does your daughter feel threatened by this schmuck?”
No, pretty sure she could kick his ass. This is a STEM school, remember.