One of the biggest fashion mistakes a guest can make at a wedding is trying to upstage the bride.
Anything that will take the attention away from a woman on the most momentous day of her life is a big no-no.
So a dress marketed as a "mother-of-the-bride outfit" probably shouldn't be a black plunging, low back number with a boosted bustier and sheer lace panels, right?
The sexy dress in question was made by Bulgarian designer Tonena, and is causing a major stir on social media, with people in awe of the bold fashion statement.
The dress also features removable sleeves and a back that could be left open or closed, from those "aiming for a more conservative look".
However Twitter commentators appeared to be loving the less-than-wedding-appropriate dress, with some comparing it to villainous characters Maleficent, Moira Rose from Schitt's Creek and Cruella de Vil.
One woman who wasn't keen on the dress suggested she might add it to her "no-no page" for her wedding, just in case anyone was inspired by the saucy number.
Another wrote she was going to get the dress and wear it to: "chaperone my sons to their first school mixer in a few years".
If you too are feeling inspired, the floor-length mermaid dress with cost you $3481, and for that price it better be serving up some serious vibes.