The secret to cleaning grease off of walls painted with semigloss paint would be to start with a gentle cleaner and work your way up to the strong ones. Grease does not stick well to semigloss paint, and gentle detergents are less likely to etch the end and rub pigment.
On the Mild Side
There is no gentler cleaning solution than warm water, which may be all you require. It might just move the grease around and make the wall dirtier, though, so try it first by rubbing an inconspicuous part of the wall using a sponge. Insert a oz of all-purpose nonabrasive cleaner or dish detergent per gallon of warm water should you have to fortify the mixture.
Kitchen grease may call for a more powerful cleaning solution. White vinegar is a mld acid which cuts grease, so try adding 1/2 cup to your own detergent solution. Make the solution much more powerful, if necessary, by blending in a cup of ammonia and 1/4 cup baking soda. Use the solution generously, but rinse the wall with clear water and dry it using a cloth afterward.