The Unladylike achievement or trophy is one of the many secrets you can unlock in Little Nightmares II. It is worth 30 gamerscore to Xbox users and a silver trophy to PlayStation owners, and earning it will help you on your way to attaining 100% completion.
To unlock the Unladylike achievement, you will need to reach chapter four. Once the Thin Man has kidnapped Six, you must traverse a rooftop section alone. Eventually, you will come across a clothes hangar that you can use to glide down a telephone wire. Head down until you smash through some wooden shutters into a new building.
Before you press on to rescue Six, head back through the window. Drop down onto the rooftop and walk backwards to spot another window. Jump up to grab the ledge and climb inside.
You will see a porcelain doll next to a Glitching Remain. The doll is a throwback to Lady, the main antagonist in Little Nightmares. To unlock the achievement, pick the doll up and throw it so that it smashes into pieces. The tagline of the achievement or trophy reads ‘Hello, have we met?’, which is a fun nod to Six encountering Lady in the previous game.