Mrs Blac Kardashian? Rob 'is talking to Chyna about getting married' .

Rob Kardashian sent out a nasty Instagram to his followers on Tuesday evening, revealing he has dropped his family for his girlfriend Blac Chyna, making him an 'orphan.'

Rob is not only going to get a tattoo for her, but he is already 'talking about a proposal.'

A walk down the aisle? Rob Kardashian wants to propose to girlfriend of one month Blac Chyna, according to a Wednesday report from UsWeekly

'He feels he's never been this into a girl and that she's the one for life,' a source said.

The two - who have been living in Calabasas together - have been dating for only one month, much to the chagrin of Kylie Jenner, 18, whose boyfriend Tyga has a child (King Cairo, aged three) with Blac.

So far Chyna has changed his life dramatically. He is no longer a recluse living at sister Khloe's mansion and he has lost 40 pounds thanks to diet and exercise, which is a big bonus because he has diabetes. 

He's hooked: 'He feels he's never been this into a girl and that she's the one for life,' a source said 

'She makes him feel secure, so now he's not hiding,' said a pal. 

But the family worries this could not end up well. 'He falls fast,' said a friend. 'But they are very much in love. He spends a lot of time at her house. She won't let him go.'

Though Rob seems to have come out of a dark place thanks to Blac, he is as acid-tongued as ever. 

The note he sent out to his 4.8 million Instagram followers was proof of that.

The full entry read: 'When the p***y good but your family don't like her so you drop your family and become an orphan.' 

Foul-mouthed humour: Rob Kardashian appears prepared to complicate things further as he posted a foul-mouthed quote on Instagram referring to his new girlfriend Black Chyna and his famous family

The post will no doubt cause shockwaves among both fans and Rob's family as his relationship with the curvaceous model has caused great friction. 

The Instagram snap amassed nearly 30,000 comments from fans within just three hours of going live - with many followers blasting the star for his seeming disloyalty.