Hermit by Chris McQueer

Since dropping out of school three years ago with no qualifications, no pals, and no ambition, Jamie Skelton spends most of his days asleep and most of his nights wanking, playing video games with his online friend, Lee, and occasionally making the journey downstairs to the kitchen for a microwave burger. 
Fiona, Jamie's maw, is trying her best, but since finding the courage to kick out her abusive husband her confidence has never recovered. She knows their lives can't carry on like this, but she's at a loss to know how to change things.
 
When Fiona tries to get Jamie to apply for a job, he sees her as the cause for all of his problems. Then Lee tells Jamie he's realised there's a name for what they are - incels - and that there's a guy he's met through the forums they can go stay with in London, to get away from their nagging mams. But in running away from his problems at home, Jamie may actually be running towards something much worse.