Britney Spears flashes under-boob cleavage in sheer black dress and models three other flirty frocks on Halloween

Britney Spears celebrated Halloween by hosting a fashion show of sorts at her $11.8 million Calabasas mansion for the viewing pleasure of her 42.4 million followers on Instagram.

In the First Of the three videos the 41-year-old Grammy winner posted Tuesday night, she showed off significant cleavage under the breasts while wearing a sheer black dress with sexy cutouts.

Britney – whose third husband Sam Asghari archived before divorcing her in August – modeled the mesh creation while performing on Janet Jackson’s 1993 song You Want This.

Spears then changed into a mini dress with a silver glitter top as she posed in front of her stripper pole.

'Hi!'  Britney Spears celebrated Halloween by staging a fashion show of sorts at her $11.8 million Calabasas mansion for the viewing pleasure of her captive 42.4 million Instagram followers

‘Hi!’ Britney Spears celebrated Halloween by staging a fashion show of sorts at her $11.8 million Calabasas mansion for the viewing pleasure of her captive 42.4 million Instagram followers

The semi-retired pop star left little to the imagination in a completely sheer dress with side slits and three silver chains draped over her bare hips.

Britney cradled one of her five dogs – a Maltese named Lacey Loo – on her bikini-clad chest in the clip set to J Balvin and Willy William’s 2017 song Mi Gente.

Then spears slipped her slim 6-foot figure in a red dress, exposing her arm, abs and legs as she poses in front of her Christmas tree in a clip to Madonna’s 2012 song I’m Addicted.

The Hold Me Closer hitmaker’s critically acclaimed memoir, The Woman In Me, has sold 400,000 copies since hitting shelves a week ago, according to TMZ.

Simon & Schuster paid Britney a $12.5 million advance (25% of net profits) to write the 288-page tell-all with three “collaborators” or ghostwriters.

Two people close to the project told the New York Times on Tuesday that author Ada Calhoun “helped create the first draft” and author Sam Lansky was “the next to join” The Woman In Me team.

“The book was completed with the help of Luke Dempsey,” the insider told the magazine of the eventual contributing author.

Dress #1!  In the first of three videos the 41-year-old Grammy winner posted Tuesday night, she showed off substantial cleavage below the breasts

She wore a sheer black dress with sexy cutouts

Dress #1! In the first of three videos the 41-year-old Grammy winner posted Tuesday night, she showed off substantial cleavage under the breasts while wearing a sheer black dress with sexy cutouts.

Fashion!  Britney - whose third husband Sam Asghari filed for divorce from her in August - modeled the mesh creation while belting out Janet Jackson's 1993 song You Want This

Fashion! Britney – whose third husband Sam Asghari filed for divorce from her in August – modeled the mesh creation while belting out Janet Jackson’s 1993 song You Want This

Dress #2!  Spears then changed into a mini dress with a silver glitter top as she posed in front of her stripper pole

Dress #2! Spears then changed into a mini dress with a silver glitter top as she posed in front of her stripper pole

Dress #3!  The semi-retired pop star left little to the imagination in a completely sheer dress with side slits

The dress had three silver chains draped over her bare hips

Dress #3! The semi-retired pop star left little to the imagination in a completely sheer side-slit dress with three silver chains draped over her bare hips

Fluffy accessory: Britney cradled one of her five dogs – a Maltese named Lacey Loo – on her bikini-clad chest in the clip set to J Balvin and Willy William's 2017 song Mi Gente

Fluffy accessory: Britney cradled one of her five dogs – a Maltese named Lacey Loo – on her bikini-clad chest in the clip set to J Balvin and Willy William’s 2017 song Mi Gente

Dress #4!  Spears then donned her slim 6-foot figure in a red dress, exposing her arm, abs and legs as she posed in front of her Christmas tree in a clip to Madonna's 2012 song I'm Addicted.

Dress #4! Spears then donned her slim 6-foot figure in a red dress, exposing her arm, abs and legs as she posed in front of her Christmas tree in a clip to Madonna’s 2012 song I’m Addicted.