Well, that's not Royal behaviour! Pippa Middleton's future brother-in-law Spencer Matthews strips down to his underwear as he poses alongside topless women in shop window

His brother, James Spencer, is set to be counted among some of the nation's most exclusive circles, after announcing his engagement to Pippa Middleton.

But while his brother may soon count the Duchess of Cambridge as a sister-in-law, Spencer Matthews is showing that he's not shy about engaging in risque behaviour.

On Friday morning, the former Made In Chelsea star was spotted posing alongside topless women in a London shop window as they took part in an event for Lyst.

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Bare all: Spencer Matthews was seen posing in a shop window alongside topless models for a new pre-London Fashion Week campaign on Friday morning

Bare all: Spencer Matthews was seen posing in a shop window alongside topless models for a new pre-London Fashion Week campaign on Friday morning

The upscale shopping site launched its 'augmented reality dressing experience', and handsome Spencer did his bit for promotion by posing in nude underwear. 

Lyst's eye-catching event allowed users to dress the near-naked model in clothes of their choice from their tablets or mobile phones. 

The tanned TV star smiled broadly as he stood sandwiched between two partially-nude women, while another man wearing just his underwear joined them. 

Pants! The former Made In Chelsea star donned nude underwear for his daring day of work

Pants! The former Made In Chelsea star donned nude underwear for his daring day of work

Miles of smiles: The reality TV personality was all smiles as he posed in the London shopfront

Miles of smiles: The reality TV personality was all smiles as he posed in the London shopfront

Virtual reality: As part of the campaign for online retailer Lyst, members of the public could virtually dress the models from their tablets and mobile phones

Virtual reality: As part of the campaign for online retailer Lyst, members of the public could virtually dress the models from their tablets and mobile phones

Lyst's official Twitter account shared images of the event, held as London Fashion Week prepares to kick off.

In one, showing Spencer flexing with all his might, Lyst playfully announced that the ex-boyfriend of Vicky Pattison was wearing the 'Emperor's New Clothes'.

In July, Pippa shared the happy news that she was set to wed her beau James after the 40-year-old popped the question.

They've got some front! The models boldly stood in the shop front waiting to be dressed

They've got some front! The models boldly stood in the shop front waiting to be dressed

He's got sole: Spencer kept his feet warm with a pair of fashionable sliders and white socks
Placement: Strategically-placed letters on the shop window made it appear as though the models were completely nude

He's got sole: Spencer kept his feet warm with a pair of fashionable sliders and white socks

Casually cool: One member of the public opted to dress the star in a tracksuit top with shorts

Casually cool: One member of the public opted to dress the star in a tracksuit top with shorts

Lady in red: The female model beside Spencer was virtually dressed in a plunging red gown

Lady in red: The female model beside Spencer was virtually dressed in a plunging red gown

Baby, it's cold outside! While London endured autumn rain, Spencer looked warm and cosy

Baby, it's cold outside! While London endured autumn rain, Spencer looked warm and cosy

A spokesman for the Cambridges said at the time: 'The Duke and Duchess of Cambridge are absolutely delighted with the news.'

The lovebirds are set to wed in 2017 - in what is set to be one of the most talked about society weddings since William and Kate tied the knot five years ago.

James asked Pippa's father for permission for his daughter's hand before popping the question.

'James is a traditionalist and very much wanted to do things properly. That meant getting his future father in law's consent,' a friend of the couple told the Daily Mail. 

The ex factor: The star counts Vicky Pattison among his list of ex-girlfriends

The ex factor: The star counts Vicky Pattison among his list of ex-girlfriends

Toned and ready: Spencer merrily showed off his taut physique during the unusual campaign

Toned and ready: Spencer merrily showed off his taut physique during the unusual campaign

Pros: The stars remained consummate professionals throughout the experimental session

Pros: The stars remained consummate professionals throughout the experimental session

Royal connections: Spencer's brother James proposed to Pippa Middleton in July of this year

Royal connections: Spencer's brother James proposed to Pippa Middleton in July of this year

The wedding of the year: Pippa and James are expected to tie the knot in 2017

The wedding of the year: Pippa and James are expected to tie the knot in 2017

It couple: James Spencer and Pippa Middleton have become London society's new it couple

It couple: James Spencer and Pippa Middleton have become London society's new it couple

 

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