waterfd

I am tiling a chimney breast with 7cm x 15cm tiles in brick bond. When you look at the wall near the top it angles to the right like this /. This right hand wall is fine till it reaches the angled part and then the front does not continue to be vertical so the tiles would need to be cut at an angle to follow the front of the wall this would look bad. Is it advisable to level this wall with rapid set before tiling? The depth would be about 1cm at it's wides part.