This can be cleaned by rubbing a pea-sized drop of bleach-free liquid dish soap with soft toothbrush on the affected area. Wipe the area then with a slightly wet piece of cloth. If this does not work you can try rubbing alcohol or a non-acetone nail polish remover. However consult the supplier of the sofa before you try these steps as different types of inks have different stain removal methods.

Use good leather cleaner which is easily available in the market and then apply a leather conditioner to restore moisture. Traditional ways of removing this is using milk or half sliced tomato. But I have never tried this.

Leather furniture is very expensive and any trail and error should be avoided. Simply contact the supplier of your sofa and ask him for remedies. They might have their own solvents to remove such stains.