A schoolgirl was not allowed to wash her hair or brush her teeth during a relationship with a jealous, possessive and controlling older boyfriend.
Tobias Coggin is said to have invaded almost every part of his victims life during their time together.
Hull Crown Court heard that the 20-year-old, who was aged between 17 and 18 at the time of the relationship, repeatedly threatened to kill himself to keep the schoolgirl under control when she tried to challenge his behaviour or end the relationship.
The girls mother, who did not know the extent of the abuse until her daughter finally found the courage to leave him, blames Coggin for her failing her GCSE exams, the court heard.
When the victim said she wanted to go to college, Coggin was so desperate to monitor what she was doing he threatened to enrol himself – even attending an open day.
She also put on weight because of the fast food Coggin insisted on.
A judge called his behaviour abhorrent and warned the 20-year-old if he ever did it again he would be going straight to prison.
But Judge David Tremberg said he was able to suspend the sentence because Coggin, who was aged between 17 and 18 at the time, was of positive good character, and pleaded guilty.
Charlotte Baines, prosecuting, said when the pair first met Coggin would pick her up in his car and take her to McDonalds.
They began a relationship weeks later, and at first things were OK, but then she began to notice changes.
He was difficult about her talking to male friends, and eventually she had to block them on social media. She also lost contact with female friends and became isolated.
Coggin would also not let her bath on her own unless he was sat on the toilet seat watching her.
If he got out of the bath before she had time to wash her hair, she had to get out anyway, with Coggin saying if she had greasy hair, at least nobody at school would fancy her.
As well as stopping her brushing her teeth, Coggin also prevented the girl wearing clean clothes.
Miss Baines said when she told him this made her feel dirty, Coggin said he did not care, she was with him and did not need anybody else.
She said: He would talk about their relationship being permanent; they would get married and have children.
The victim said she was only 16 and would soon be going to college.
After dropping her at home, Coggin would make the girl Face Time him until she fell asleep, otherwise he would accuse her of going out and cheating on him.
When the girl did end the relationship, Coggin sprayed WD40 into his mouth in an attempt to stop [her] leaving him, but she had the courage to walk away.
In his police interview, Coggin produced a prepared statement and blamed the girl for causing arguments. He later admitted two offences of coercive and controlling behaviour, and was sentenced to five months in a young offender institution, suspended for two
The maximum sentence is five years.
Paul Genney, mitigating, said: This was an obsessive adolescent relationship. He says, he instructs, that hes ashamed of his behaviour as it was then.
Hes a different person, effectively, to what he was then.
Coggin was made subject to as two-year restraining order, must have up to 30 days rehabilitation, and attend a relationships course.